diff --git a/docs/docs_requirements.txt b/docs/docs_requirements.txt
index 66b07d7..4b32a7c 100644
--- a/docs/docs_requirements.txt
+++ b/docs/docs_requirements.txt
@@ -1,4 +1,6 @@
+sphinx==8.1.3
 sphinx-rtd-theme>=2.0.0
 nbsphinx
 sphinx_copybutton
 ipython>=8.17
+