diff --git a/src/tools/qdoc/cppcodeparser.cpp b/src/tools/qdoc/cppcodeparser.cpp
index f20b998cc44..0405cc2c2ba 100644
--- a/src/tools/qdoc/cppcodeparser.cpp
+++ b/src/tools/qdoc/cppcodeparser.cpp
@@ -833,6 +833,10 @@ void CppCodeParser::processQmlProperties(const Doc& doc,
                     }
                 }
             }
+        } else if (qpgn) {
+            doc.startLocation().warning(
+                tr("Invalid use of '\\%1'; not allowed in a '\\%2'").arg(
+                    topic, qmlPropertyGroupTopic.topic));
         }
     }
 }