diff --git a/docs/conf.py b/docs/conf.py
index 394ad60..8237f55 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -62,7 +62,7 @@
 #
 # This is also used if you do content translation via gettext catalogs.
 # Usually you set "language" from the command line for these cases.
-language = None
+language = 'en'
 
 # List of patterns, relative to source directory, that match files and
 # directories to ignore when looking for source files.
diff --git a/requirements.txt b/requirements.txt
index 6215406..7fbec45 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -4,5 +4,5 @@ pytest>=4.6
 pytest-xdist[psutil]
 mock
 pytest-cov
-sphinx==4.2.0
+sphinx==5.0.2
 scipy;python_version<"3.10"
diff --git a/setup.py b/setup.py
index f9249ce..7db547c 100644
--- a/setup.py
+++ b/setup.py
@@ -27,12 +27,12 @@ def get_version(rel_path):
     'pytest-xdist[psutil]',
     'mock',
     'pytest-cov',
-    'sphinx==4.2.0',
+    "sphinx==5.0.2",
     'scipy;python_version<"3.10"',
     ]
 
 DOCS_REQUIRES = [
-    "sphinx==4.2.0",
+    "sphinx==5.0.2",
     "pydata-sphinx-theme==0.7.2",
     "nbsphinx",
     ]