diff --git a/accessible/src/base/nsAccessNode.h b/accessible/src/base/nsAccessNode.h
index fef2d2ae0406..beed6774cf74 100644
--- a/accessible/src/base/nsAccessNode.h
+++ b/accessible/src/base/nsAccessNode.h
@@ -68,10 +68,6 @@ public:
   {
     return GetNode() && GetNode()->IsNodeOfType(nsINode::eCONTENT);
   }
-  bool IsDocumentNode() const
-  {
-    return GetNode() && GetNode()->IsNodeOfType(nsINode::eDOCUMENT);
-  }
 
   /**
    * Return the unique identifier of the accessible.
diff --git a/accessible/src/base/nsTextEquivUtils.cpp b/accessible/src/base/nsTextEquivUtils.cpp
index 07c8482e90ef..959ba54738d4 100644
--- a/accessible/src/base/nsTextEquivUtils.cpp
+++ b/accessible/src/base/nsTextEquivUtils.cpp
@@ -265,7 +265,7 @@ nsTextEquivUtils::AppendFromValue(Accessible* aAccessible,
   }
 
   //XXX: is it necessary to care the accessible is not a document?
-  if (aAccessible->IsDocumentNode())
+  if (aAccessible->IsDoc())
     return NS_ERROR_UNEXPECTED;
 
   nsIContent *content = aAccessible->GetContent();
diff --git a/accessible/src/generic/Accessible.cpp b/accessible/src/generic/Accessible.cpp
index d0554855c22e..7b45e9eb89cc 100644
--- a/accessible/src/generic/Accessible.cpp
+++ b/accessible/src/generic/Accessible.cpp
@@ -3038,7 +3038,7 @@ Accessible::ContainerWidget() const
       }
 
       // Don't cross DOM document boundaries.
-      if (parent->IsDocumentNode())
+      if (parent->IsDoc())
         break;
     }
   }