diff --git a/doc/requirements.txt b/doc/requirements.txt
index 6b57f159d..fe22670be 100644
--- a/doc/requirements.txt
+++ b/doc/requirements.txt
@@ -1,5 +1,5 @@
 nnabla==1.36.0
-Sphinx
+Sphinx<7
 sphinx-rtd-theme
 mock
 pillow<10.0
diff --git a/doc/requirements.txt.tmpl b/doc/requirements.txt.tmpl
index ed50ab36c..b6d7fcd37 100644
--- a/doc/requirements.txt.tmpl
+++ b/doc/requirements.txt.tmpl
@@ -1,5 +1,5 @@
 nnabla==${'.'.join(version.split('.')[:3])}
-Sphinx
+Sphinx<7
 sphinx-rtd-theme
 mock
 pillow<10.0
@@ -7,7 +7,7 @@ alabaster
 commonmark
 recommonmark
 readthedocs-sphinx-ext
-jinja2
+jinja2>3.1.0
 sphinxcontrib-actdiag
 sphinxcontrib-blockdiag
 sphinxcontrib-nwdiag