diff --git a/gnu/packages/python.scm b/gnu/packages/python.scm
index 2f3d2b36ac..700e792143 100644
--- a/gnu/packages/python.scm
+++ b/gnu/packages/python.scm
@@ -2843,6 +2843,8 @@ sources.")
         (base32
          "19nw3rn7awplcdrz63kg1njqwkbymfg9lwn7l2grhdyhyr2gaa8g"))))
     (build-system python-build-system)
+    (propagated-inputs
+     `(("python-sphinx" ,python-sphinx)))
     (home-page "https://github.com/snide/sphinx_rtd_theme/")
     (synopsis "ReadTheDocs.org theme for Sphinx")
     (description "A theme for Sphinx used by ReadTheDocs.org.")