diff --git a/lcl/dbgrids.pas b/lcl/dbgrids.pas
index 370c9c9a04..99f12900b0 100644
--- a/lcl/dbgrids.pas
+++ b/lcl/dbgrids.pas
@@ -3160,7 +3160,7 @@ begin
     try
       inherited Assign(Source);
       FieldName := TColumn(Source).FieldName;
-      DisplayFormat := TColumn(Source).FieldName;
+      DisplayFormat := TColumn(Source).DisplayFormat;
       ValueChecked := TColumn(Source).ValueChecked;
       ValueUnchecked := TColumn(Source).ValueUnchecked;
     finally