diff --git a/packages/x-data-grid/src/hooks/features/rowSelection/utils.ts b/packages/x-data-grid/src/hooks/features/rowSelection/utils.ts
index ce2aa20c4e3b..6084acb11686 100644
--- a/packages/x-data-grid/src/hooks/features/rowSelection/utils.ts
+++ b/packages/x-data-grid/src/hooks/features/rowSelection/utils.ts
@@ -87,8 +87,8 @@ export function getCheckboxPropsSelector(groupId: GridRowId, autoSelectParents:
       }
       return {
         isIndeterminate:
-          (selectedDescendantsCount > 0 && selectedDescendantsCount < selectableDescendantsCount) ||
-          (selectedDescendantsCount === selectableDescendantsCount &&
+          selectedDescendantsCount > 0 &&
+          (selectedDescendantsCount < selectableDescendantsCount ||
             rowSelectionLookup[groupId] === undefined),
         isChecked: autoSelectParents
           ? selectedDescendantsCount > 0