diff --git a/lisa/commands.py b/lisa/commands.py
index 50812bcd1..fd7f45f80 100644
--- a/lisa/commands.py
+++ b/lisa/commands.py
@@ -24,9 +24,7 @@ def run(args: Namespace) -> int:
 
     notifier_data = builder.partial_resolve(constants.NOTIFIER)
     if notifier_data:
-        notifier_runbook = schema.Notifier.schema().load(  # type: ignore
-            notifier_data, many=True
-        )
+        notifier_runbook = schema.load_by_type_many(schema.Notifier, notifier_data)
         notifier.initialize(runbooks=notifier_runbook)
     run_message = notifier.TestRunMessage(
         test_project=builder.partial_resolve(constants.TEST_PROJECT),
diff --git a/lisa/parameter_parser/runbook.py b/lisa/parameter_parser/runbook.py
index f7ddc92f5..55b2b11b5 100644
--- a/lisa/parameter_parser/runbook.py
+++ b/lisa/parameter_parser/runbook.py
@@ -226,7 +226,7 @@ class RunbookBuilder:
             and data_from_include[constants.VARIABLE]
         ):
             variables_from_include = [
-                schema.Variable.schema().load(variable)  # type: ignore
+                schema.load_by_type(schema.Variable, variable)
                 for variable in data_from_include[constants.VARIABLE]
             ]
             # resolve to absolute path
@@ -238,7 +238,7 @@ class RunbookBuilder:
             and data_from_current[constants.VARIABLE]
         ):
             variables_from_current: List[schema.Variable] = [
-                schema.Variable.schema().load(variable)  # type: ignore
+                schema.load_by_type(schema.Variable, variable)
                 for variable in data_from_current[constants.VARIABLE]
             ]
 
@@ -345,7 +345,7 @@ class RunbookBuilder:
             for include_raw in includes:
                 try:
                     include: schema.Include
-                    include = schema.Include.schema().load(include_raw)  # type: ignore
+                    include = schema.load_by_type(schema.Include, include_raw)
                 except Exception as identifer:
                     raise LisaException(
                         f"error on loading include node [{include_raw}]: {identifer}"
diff --git a/lisa/platform_.py b/lisa/platform_.py
index de680237c..d84b5e075 100644
--- a/lisa/platform_.py
+++ b/lisa/platform_.py
@@ -195,8 +195,6 @@ def load_platform(platforms_runbook: List[schema.Platform]) -> Platform:
 
 def load_platform_from_builder(runbook_builder: RunbookBuilder) -> Platform:
     platform_runbook_data = runbook_builder.partial_resolve(constants.PLATFORM)
-    platform_runbook = schema.Platform.schema().load(  # type: ignore
-        platform_runbook_data, many=True
-    )
+    platform_runbook = schema.load_by_type_many(schema.Platform, platform_runbook_data)
     platform = load_platform(platform_runbook)
     return platform
diff --git a/lisa/runner.py b/lisa/runner.py
index 2b7563a3a..af5b0e0fb 100644
--- a/lisa/runner.py
+++ b/lisa/runner.py
@@ -210,7 +210,7 @@ class RootRunner(Action):
         runner_filters: Dict[str, List[schema.BaseTestCaseFilter]] = {}
         for raw_filter in runbook.testcase_raw:
             # by default run all filtered cases unless 'enable' is specified as false
-            filter = schema.BaseTestCaseFilter.schema().load(raw_filter)  # type:ignore
+            filter = schema.load_by_type(schema.BaseTestCaseFilter, raw_filter)
             if filter.enable:
                 raw_filters: List[schema.BaseTestCaseFilter] = runner_filters.get(
                     filter.type, []
diff --git a/lisa/runners/lisa_runner.py b/lisa/runners/lisa_runner.py
index 8e1f35090..e2e12c1d1 100644
--- a/lisa/runners/lisa_runner.py
+++ b/lisa/runners/lisa_runner.py
@@ -608,10 +608,8 @@ class LisaRunner(BaseRunner):
                         node_requirement_data = deep_update_dict(
                             platform_requirement_data, node_requirement_data
                         )
-                        node_requirement = (
-                            schema.NodeSpace.schema().load(  # type: ignore
-                                node_requirement_data
-                            )
+                        node_requirement = schema.load_by_type(
+                            schema.NodeSpace, node_requirement_data
                         )
                         environment_requirement.nodes[index] = node_requirement
 
diff --git a/lisa/schema.py b/lisa/schema.py
index 8d83a8dbe..f9879e661 100644
--- a/lisa/schema.py
+++ b/lisa/schema.py
@@ -120,8 +120,8 @@ class ExtendableSchemaMixin:
                 runbook_type=runbook_type, type_name=type_name
             )
             if self.extended_schemas and type_name in self.extended_schemas:
-                self._extended_runbook: T = runbook_type.schema().load(  # type:ignore
-                    self.extended_schemas[type_name]
+                self._extended_runbook: T = load_by_type(
+                    runbook_type, self.extended_schemas[type_name]
                 )
             else:
                 # value may be filled outside, so hold and return an object.
@@ -266,7 +266,7 @@ class Extension:
             if isinstance(extension, str):
                 extension = Extension(path=extension)
             elif isinstance(extension, dict):
-                extension = Extension.schema().load(extension)  # type: ignore
+                extension = load_by_type(Extension, extension)
             results.append(extension)
 
         return results
@@ -324,10 +324,7 @@ class Variable:
         if isinstance(self.value_raw, dict):
             self.value: Union[
                 str, bool, int, VariableEntry, List[Union[str, bool, int]]
-            ] = cast(
-                VariableEntry,
-                VariableEntry.schema().load(self.value_raw),  # type:ignore
-            )
+            ] = load_by_type(VariableEntry, self.value_raw)
         else:
             self.value = self.value_raw
 
@@ -676,18 +673,14 @@ class Environment:
             for node_raw in self.nodes_raw:
                 node_type = node_raw[constants.TYPE]
                 if node_type == constants.ENVIRONMENTS_NODES_REQUIREMENT:
-                    original_req: NodeSpace = NodeSpace.schema().load(  # type:ignore
-                        node_raw
-                    )
+                    original_req: NodeSpace = load_by_type(NodeSpace, node_raw)
                     expanded_req = original_req.expand_by_node_count()
                     if self.nodes_requirement is None:
                         self.nodes_requirement = []
                     self.nodes_requirement.extend(expanded_req)
                 else:
                     # load base schema for future parsing
-                    node: Node = Node.schema().load(  # type:ignore
-                        node_raw
-                    )
+                    node: Node = load_by_type(Node, node_raw)
                     results.append(node)
             self.nodes_raw = None
 
@@ -764,7 +757,7 @@ class Platform(TypedSchema, ExtendableSchemaMixin):
         # But the schema will be validated here. The original NodeSpace object holds
         if self.requirement:
             # validate schema of raw inputs
-            Capability.schema().load(self.requirement)  # type: ignore
+            load_by_type(Capability, self.requirement)
 
 
 @dataclass_json()
@@ -916,3 +909,26 @@ class Runbook:
                 }
             ]
         self.testcase: List[Any] = []
+
+
+def load_by_type(schema_type: Type[T], raw_runbook: Any, many: bool = False) -> T:
+    """
+    Convert dict, list or base typed schema to specified typed schema.
+    """
+    if type(raw_runbook) == schema_type:
+        return raw_runbook
+
+    if not isinstance(raw_runbook, dict) and not many:
+        raw_runbook = raw_runbook.to_dict()
+
+    result: T = schema_type.schema().load(raw_runbook, many=many)  # type: ignore
+    return result
+
+
+def load_by_type_many(schema_type: Type[T], raw_runbook: Any) -> List[T]:
+    """
+    Convert raw list to list of typed schema. It has different returned type
+    with load_by_type.
+    """
+    result = load_by_type(schema_type, raw_runbook=raw_runbook, many=True)
+    return cast(List[T], result)
diff --git a/lisa/sut_orchestrator/azure/common.py b/lisa/sut_orchestrator/azure/common.py
index 365eb86e6..4fc568257 100644
--- a/lisa/sut_orchestrator/azure/common.py
+++ b/lisa/sut_orchestrator/azure/common.py
@@ -132,8 +132,8 @@ class AzureNodeSchema:
                 self.marketplace_raw = dict(
                     (k, v.lower()) for k, v in self.marketplace_raw.items()
                 )
-                marketplace = AzureVmMarketplaceSchema.schema().load(  # type: ignore
-                    self.marketplace_raw
+                marketplace = schema.load_by_type(
+                    AzureVmMarketplaceSchema, self.marketplace_raw
                 )
                 # this step makes marketplace_raw is validated, and
                 # filter out any unwanted content.
@@ -193,11 +193,11 @@ class AzureNodeSchema:
             self.shared_gallery_raw = dict(
                 (k, v.lower()) for k, v in self.shared_gallery_raw.items()
             )
-            shared_gallery = SharedImageGallerySchema.schema().load(  # type: ignore
-                self.shared_gallery_raw
+            shared_gallery = schema.load_by_type(
+                SharedImageGallerySchema, self.shared_gallery_raw
             )
-            if not shared_gallery.subscription_id:  # type: ignore
-                shared_gallery.subscription_id = self.subscription_id  # type: ignore
+            if not shared_gallery.subscription_id:
+                shared_gallery.subscription_id = self.subscription_id
             # this step makes shared_gallery_raw is validated, and
             # filter out any unwanted content.
             self.shared_gallery_raw = shared_gallery.to_dict()  # type: ignore
diff --git a/lisa/sut_orchestrator/azure/platform_.py b/lisa/sut_orchestrator/azure/platform_.py
index 61cf2a690..0a62fd671 100644
--- a/lisa/sut_orchestrator/azure/platform_.py
+++ b/lisa/sut_orchestrator/azure/platform_.py
@@ -723,9 +723,7 @@ class AzurePlatform(Platform):
             try:
                 with open(cached_file_name, "r") as f:
                     loaded_data: Dict[str, Any] = json.load(f)
-                loaded_obj = AzureLocation.schema().load(  # type:ignore
-                    loaded_data
-                )
+                loaded_obj = schema.load_by_type(AzureLocation, loaded_data)
             except Exception as identifier:
                 # if schema changed, There may be exception, remove cache and retry
                 # Note: retry on this method depends on decorator
diff --git a/lisa/transformer.py b/lisa/transformer.py
index 594b7dfcc..6db8f7382 100644
--- a/lisa/transformer.py
+++ b/lisa/transformer.py
@@ -142,8 +142,8 @@ def _run_transformers(
     transformers_runbook: List[schema.Transformer] = []
     for runbook_data in transformers_data:
         # get base transformer runbook for replacing variables.
-        runbook: schema.Transformer = schema.Transformer.schema().load(  # type: ignore
-            runbook_data
+        runbook: schema.Transformer = schema.load_by_type(
+            schema.Transformer, runbook_data
         )
 
         if runbook.enabled:
@@ -165,7 +165,7 @@ def _run_transformers(
         replace_variables(runbook_data, copied_variables)
 
         # revert to runbook
-        runbook = schema.Transformer.schema().load(runbook_data)  # type: ignore
+        runbook = schema.load_by_type(schema.Transformer, runbook_data)
 
         derived_builder = runbook_builder.derive(copied_variables)
         transformer = factory.create_by_runbook(
diff --git a/lisa/util/subclasses.py b/lisa/util/subclasses.py
index 2ebd3f872..d77199eea 100644
--- a/lisa/util/subclasses.py
+++ b/lisa/util/subclasses.py
@@ -20,7 +20,7 @@ class BaseClassWithRunbookMixin(BaseClassMixin):
     ) -> "BaseClassWithRunbookMixin":
         if cls.type_schema() != type(runbook):
             # reload if type is defined in subclass
-            runbook = cls.type_schema().schema().load(runbook.to_dict())  # type:ignore
+            runbook = schema.load_by_type(cls.type_schema(), runbook)
         return cls(runbook=runbook, **kwargs)
 
     @classmethod
@@ -72,7 +72,7 @@ class Factory(InitializableMixin, Generic[T_BASECLASS], SubClassTypeDict):
             raise LisaException(
                 f"cannot find subclass '{type_name}' of {self._base_type.__name__}"
             )
-        instance = sub_type.schema().load(raw_runbook)  # type: ignore
+        instance: Any = schema.load_by_type(sub_type, raw_runbook)
         if hasattr(instance, "extended_schemas"):
             if instance.extended_schemas:
                 raise LisaException(
diff --git a/lisa/variable.py b/lisa/variable.py
index cf6a2face..7da05a00a 100644
--- a/lisa/variable.py
+++ b/lisa/variable.py
@@ -4,7 +4,7 @@
 import os
 import re
 from dataclasses import dataclass
-from typing import Any, Dict, List, Optional, Union, cast
+from typing import Any, Dict, List, Optional, Union
 
 import yaml
 
@@ -142,10 +142,8 @@ def _load_from_runbook(
     current_variables = higher_level_variables.copy()
 
     if constants.VARIABLE in runbook_data:
-        variable_entries: List[
-            schema.Variable
-        ] = schema.Variable.schema().load(  # type:ignore
-            runbook_data[constants.VARIABLE], many=True
+        variable_entries: List[schema.Variable] = schema.load_by_type_many(
+            schema.Variable, runbook_data[constants.VARIABLE]
         )
 
         left_variables = variable_entries.copy()
@@ -262,10 +260,7 @@ def load_from_variable_entry(
         value = raw_value
     else:
         if isinstance(raw_value, dict):
-            raw_value = cast(
-                schema.VariableEntry,
-                schema.VariableEntry.schema().load(raw_value),  # type: ignore
-            )
+            raw_value = schema.load_by_type(schema.VariableEntry, raw_value)
         is_secret = is_secret or raw_value.is_secret
         mask_pattern_name = raw_value.mask
         value = raw_value.value
diff --git a/selftests/test_env_requirement.py b/selftests/test_env_requirement.py
index 7e8da98ed..3a70a8316 100644
--- a/selftests/test_env_requirement.py
+++ b/selftests/test_env_requirement.py
@@ -116,40 +116,46 @@ class RequirementTestCase(SearchSpaceTestCase):
     def test_supported_simple_requirement(self) -> None:
         n1 = schema.NodeSpace()
         n1 = n1.generate_min_capability(n1)
-        n4 = schema.NodeSpace.schema().load(  # type:ignore
-            {"type": constants.ENVIRONMENTS_NODES_REQUIREMENT, "core_count": 4}
+        n4 = schema.load_by_type(
+            schema.NodeSpace,
+            {"type": constants.ENVIRONMENTS_NODES_REQUIREMENT, "core_count": 4},
         )
         n4 = n4.generate_min_capability(n4)
-        n4g1 = schema.NodeSpace.schema().load(  # type:ignore
+        n4g1 = schema.load_by_type(
+            schema.NodeSpace,
             {
                 "type": constants.ENVIRONMENTS_NODES_REQUIREMENT,
                 "core_count": 4,
                 "gpu_count": 1,
-            }
+            },
         )
         n4g1 = n4g1.generate_min_capability(n4g1)
-        n6 = schema.NodeSpace.schema().load(  # type:ignore
-            {"type": constants.ENVIRONMENTS_NODES_REQUIREMENT, "core_count": 6}
+        n6 = schema.load_by_type(
+            schema.NodeSpace,
+            {"type": constants.ENVIRONMENTS_NODES_REQUIREMENT, "core_count": 6},
         )
         n6 = n6.generate_min_capability(n6)
-        n6g2 = schema.NodeSpace.schema().load(  # type:ignore
+        n6g2 = schema.load_by_type(
+            schema.NodeSpace,
             {
                 "type": constants.ENVIRONMENTS_NODES_REQUIREMENT,
                 "core_count": 6,
                 "gpu_count": 2,
-            }
+            },
         )
         n6g2 = n6g2.generate_min_capability(n6g2)
-        n6g1 = schema.NodeSpace.schema().load(  # type:ignore
+        n6g1 = schema.load_by_type(
+            schema.NodeSpace,
             {
                 "type": constants.ENVIRONMENTS_NODES_REQUIREMENT,
                 "core_count": 6,
                 "gpu_count": 1,
-            }
+            },
         )
         n6g1 = n6g1.generate_min_capability(n6g1)
-        n10 = schema.NodeSpace.schema().load(  # type:ignore
-            {"type": constants.ENVIRONMENTS_NODES_REQUIREMENT, "core_count": 10}
+        n10 = schema.load_by_type(
+            schema.NodeSpace,
+            {"type": constants.ENVIRONMENTS_NODES_REQUIREMENT, "core_count": 10},
         )
         n10 = n10.generate_min_capability(n10)
 
diff --git a/selftests/test_environment.py b/selftests/test_environment.py
index ac4a4e574..459aa185e 100644
--- a/selftests/test_environment.py
+++ b/selftests/test_environment.py
@@ -173,7 +173,7 @@ def generate_runbook(
             environments.append({"nodes": [n]})
 
     data = {"max_concurrency": 2, constants.ENVIRONMENTS: environments}
-    return schema.EnvironmentRoot.schema().load(data)  # type: ignore
+    return schema.load_by_type(schema.EnvironmentRoot, data)
 
 
 class EnvironmentTestCase(TestCase):
diff --git a/selftests/test_platform.py b/selftests/test_platform.py
index 83f523fe2..dd17d27e1 100644
--- a/selftests/test_platform.py
+++ b/selftests/test_platform.py
@@ -120,7 +120,7 @@ def generate_platform(
         "admin_password": admin_password,
         "admin_private_key_file": admin_key_file,
     }
-    runbook = schema.Platform.schema().load(runbook_data)  # type: ignore
+    runbook = schema.load_by_type(schema.Platform, runbook_data)
     platform = load_platform([runbook])
     platform.initialize()
     try:
diff --git a/selftests/test_transformer.py b/selftests/test_transformer.py
index d2ed6bac2..fac0dbb09 100644
--- a/selftests/test_transformer.py
+++ b/selftests/test_transformer.py
@@ -137,9 +137,7 @@ class TestTransformerCase(TestCase):
     def test_transformer_no_name(self) -> None:
         # no name, the type will be used. in name
         transformers_data: List[Any] = [{"type": MOCK, "items": {"v0": "v0_1"}}]
-        transformers = schema.Transformer.schema().load(  # type: ignore
-            transformers_data, many=True
-        )
+        transformers = schema.load_by_type_many(schema.Transformer, transformers_data)
         runbook_builder = self._generate_runbook_builder(transformers)
 
         result = transformer._run_transformers(runbook_builder)
@@ -199,10 +197,8 @@ class TestTransformerCase(TestCase):
             items: Dict[str, str] = dict()
             for item_index in range(index + 1):
                 items[f"v{item_index}"] = f"{index}_{item_index}"
-            runbook: schema.Transformer = (
-                schema.Transformer.schema().load(  # type:ignore
-                    {"type": MOCK, "name": f"t{index}", "items": items}
-                )
+            runbook: schema.Transformer = schema.load_by_type(
+                schema.Transformer, {"type": MOCK, "name": f"t{index}", "items": items}
             )
             results.append(runbook)