diff --git a/.github/dependabot.yml b/.github/dependabot.yml
index ae49d9003..71215ba0a 100644
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@@ -12,5 +12,8 @@ updates:
       # setuptools releases new versions almost daily
       - dependency-name: "setuptools"
         update-types: ["version-update:semver-patch"]
-      # segmentation-models-pytorch requires older timm, can't update
+      # Sphinx 6 is incompatible with pytorch-sphinx-theme
+      # https://github.com/pytorch/pytorch_sphinx_theme/issues/175
+      - dependency-name: "sphinx"
+      # segmentation-models-pytorch pins timm, must update in unison
       - dependency-name: "timm"
diff --git a/environment.yml b/environment.yml
index 3b5756bd3..ca1b10cc9 100644
--- a/environment.yml
+++ b/environment.yml
@@ -44,7 +44,7 @@ dependencies:
     - scipy>=1.6.2
     - segmentation-models-pytorch>=0.2
     - setuptools>=42
-    - sphinx>=4
+    - sphinx>=4,<6
     - timm>=0.4.12
     - torchmetrics>=0.10
     - zipfile-deflate64>=0.2
diff --git a/requirements/docs.txt b/requirements/docs.txt
index 27a997e08..5f5f0cb90 100644
--- a/requirements/docs.txt
+++ b/requirements/docs.txt
@@ -1,4 +1,4 @@
 # docs
 ipywidgets==8.0.4
 nbsphinx==0.8.12
-sphinx==6.1.3
+sphinx==5.3.0
diff --git a/setup.cfg b/setup.cfg
index 7ea69b52c..7ea1cb62a 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -105,7 +105,9 @@ docs =
     # release versions missing files, must install from master
     pytorch-sphinx-theme
     # sphinx 4+ required for autodoc_typehints_description_target = documented
-    sphinx>=4,<7
+    # sphinx 6+ is incompatible with pytorch-sphinx-theme
+    # https://github.com/pytorch/pytorch_sphinx_theme/issues/175
+    sphinx>=4,<6
 style =
     # black 21.8+ required for Jupyter support
     black[jupyter]>=21.8,<24