diff --git a/sphinx/builders/html/__init__.py b/sphinx/builders/html/__init__.py
index 6146201fa9b..e9622308165 100644
--- a/sphinx/builders/html/__init__.py
+++ b/sphinx/builders/html/__init__.py
@@ -571,7 +571,7 @@ def prepare_writing(self, docnames: Set[str]) -> None:
             }
         self.globalcontext |= self.config.html_context
 
-        if self.copysource:
+        if self.config.html_copy_source:
             # Create _sources
             ensuredir(self._sources_dir)