diff --git a/src/lib/litegraph/src/subgraph/SubgraphNode.ts b/src/lib/litegraph/src/subgraph/SubgraphNode.ts
index 57c86894c..8ee6dcdc6 100644
--- a/src/lib/litegraph/src/subgraph/SubgraphNode.ts
+++ b/src/lib/litegraph/src/subgraph/SubgraphNode.ts
@@ -16,7 +16,10 @@ import type {
   GraphOrSubgraph,
   Subgraph
 } from '@/lib/litegraph/src/subgraph/Subgraph'
-import type { ExportedSubgraphInstance } from '@/lib/litegraph/src/types/serialisation'
+import type {
+  ExportedSubgraphInstance,
+  ISerialisedNode
+} from '@/lib/litegraph/src/types/serialisation'
 import type { IBaseWidget } from '@/lib/litegraph/src/types/widgets'
 import type { UUID } from '@/lib/litegraph/src/utils/uuid'
 import { toConcreteWidget } from '@/lib/litegraph/src/widgets/widgetMap'
@@ -540,4 +543,36 @@ export class SubgraphNode extends LGraphNode implements BaseLGraph {
       }
     }
   }
+
+  /**
+   * Synchronizes widget values from this SubgraphNode instance to the
+   * corresponding widgets in the subgraph definition before serialization.
+   * This ensures nested subgraph widget values are preserved when saving.
+   */
+  override serialize(): ISerialisedNode {
+    // Sync widget values to subgraph definition before serialization
+    for (let i = 0; i < this.widgets.length; i++) {
+      const widget = this.widgets[i]
+      const input = this.inputs.find((inp) => inp.name === widget.name)
+
+      if (input) {
+        const subgraphInput = this.subgraph.inputNode.slots.find(
+          (slot) => slot.name === input.name
+        )
+
+        if (subgraphInput) {
+          // Find all widgets connected to this subgraph input
+          const connectedWidgets = subgraphInput.getConnectedWidgets()
+
+          // Update the value of all connected widgets
+          for (const connectedWidget of connectedWidgets) {
+            connectedWidget.value = widget.value
+          }
+        }
+      }
+    }
+
+    // Call parent serialize method
+    return super.serialize()
+  }
 }