diff --git a/packages/workflow/src/ObservableObject.ts b/packages/workflow/src/ObservableObject.ts
index 6923924374..90eec3d132 100644
--- a/packages/workflow/src/ObservableObject.ts
+++ b/packages/workflow/src/ObservableObject.ts
@@ -13,7 +13,7 @@ export function create(target: IDataObject, parent?: IObservableObject, option?:
 
 	// Make all the children of target also observeable
 	for (const key in target) {
-		if (typeof target[key] === 'object') {
+		if (typeof target[key] === 'object' && target[key] !== null) {
 			target[key] = create(target[key] as IDataObject, (parent || target) as IObservableObject, option, depth + 1);
 		}
 	}
diff --git a/packages/workflow/test/ObservableObject.test.ts b/packages/workflow/test/ObservableObject.test.ts
index ff3e3e71eb..1e4c04ca19 100644
--- a/packages/workflow/test/ObservableObject.test.ts
+++ b/packages/workflow/test/ObservableObject.test.ts
@@ -142,6 +142,15 @@ describe('ObservableObject', () => {
 		expect(testObject).toEqual({ a: {} });
 	});
 
+	test('should recognize that item on second child level changed with null (init data exists)', () => {
+		const testObject = ObservableObject.create({ a: { b: { c: null } } });
+		expect(testObject.__dataChanged).toBeFalsy();
+		expect((testObject.a! as IDataObject).b).toEqual({ c: null });
+		expect(((testObject.a! as IDataObject).b! as IDataObject).c).toEqual(null);
+		((testObject.a! as IDataObject).b! as IDataObject).c = 2;
+		expect(testObject.__dataChanged).toBeTruthy();
+		expect((testObject.a! as IDataObject).b).toEqual({ c: 2 });
+	});