diff --git a/packages/primevue/src/treetable/style/TreeTableStyle.js b/packages/primevue/src/treetable/style/TreeTableStyle.js
index 612d80652..0a8440001 100644
--- a/packages/primevue/src/treetable/style/TreeTableStyle.js
+++ b/packages/primevue/src/treetable/style/TreeTableStyle.js
@@ -35,7 +35,7 @@ const classes = {
         {
             'p-treetable-sortable-column': instance.columnProp('sortable'),
             'p-treetable-resizable-column': props.resizableColumns,
-            'p-treetable-column-sorted': instance.isColumnSorted(),
+            'p-treetable-column-sorted': instance.columnProp('sortable') ? instance.isColumnSorted() : false,
             'p-treetable-frozen-column': instance.columnProp('frozen')
         }
     ],