diff --git a/dbms/src/Interpreters/InterpreterSelectQuery.cpp b/dbms/src/Interpreters/InterpreterSelectQuery.cpp
index 14e4d15f113..6c1ef1aa5f2 100644
--- a/dbms/src/Interpreters/InterpreterSelectQuery.cpp
+++ b/dbms/src/Interpreters/InterpreterSelectQuery.cpp
@@ -1510,7 +1510,7 @@ void InterpreterSelectQuery::executeOrder(Pipeline & pipeline, SelectQueryInfo &
             settings.max_bytes_before_external_sort, context.getTemporaryPath());
     };
 
-    if (settings.optimize_pk_order)
+    if (settings.optimize_pk_order && !query.groupBy())
     {
         if (const auto * merge_tree = dynamic_cast<const MergeTreeData *>(storage.get()))
         {