diff --git a/packages/vite/src/node/server/mixedModuleGraph.ts b/packages/vite/src/node/server/mixedModuleGraph.ts
index 74000cce46e245..c133403cab67ae 100644
--- a/packages/vite/src/node/server/mixedModuleGraph.ts
+++ b/packages/vite/src/node/server/mixedModuleGraph.ts
@@ -301,7 +301,7 @@ export class ModuleGraph {
     }
     if (ssrModules) {
       for (const mod of ssrModules) {
-        if (!this._client.getModuleById(mod.id!)) {
+        if (mod.id == null || !this._client.getModuleById(mod.id)) {
           result.add(this.getBackwardCompatibleBrowserModuleNode(mod)!)
         }
       }