diff --git a/packages/x-data-grid/src/hooks/features/dimensions/useGridDimensions.ts b/packages/x-data-grid/src/hooks/features/dimensions/useGridDimensions.ts
index ef6a55b5bc802..638e052f12a33 100644
--- a/packages/x-data-grid/src/hooks/features/dimensions/useGridDimensions.ts
+++ b/packages/x-data-grid/src/hooks/features/dimensions/useGridDimensions.ts
@@ -375,7 +375,6 @@ export function useGridDimensions(apiRef: RefObject<GridPrivateApiCommunity>, pr
 
 function setCSSVariables(root: HTMLElement, dimensions: GridDimensions) {
   const set = (k: string, v: string) => root.style.setProperty(k, v);
-  set('--DataGrid-width', `${dimensions.viewportOuterSize.width}px`);
   set('--DataGrid-hasScrollX', `${Number(dimensions.hasScrollX)}`);
   set('--DataGrid-hasScrollY', `${Number(dimensions.hasScrollY)}`);
   set('--DataGrid-scrollbarSize', `${dimensions.scrollbarSize}px`);