diff --git a/doc/conf.py b/doc/conf.py
index 26d80d7..2573754 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -315,7 +315,7 @@
 # use apidoc to generate developer doc
 import os
 from os import path
-from sphinx.apidoc import main
+from sphinx.ext.apidoc import main
 
 
 rootpath = path.abspath(path.join(project_root, "src"))