diff --git a/packages/schema/src/schema.ts b/packages/schema/src/schema.ts
index 2e022bbae0..bf58f81f64 100644
--- a/packages/schema/src/schema.ts
+++ b/packages/schema/src/schema.ts
@@ -12,19 +12,21 @@ export class Schema<S extends JSONSchemaDefinition> {
   ajv: Ajv;
   validate: AsyncValidateFunction<FromSchema<S>>;
   definition: JSONSchema6;
-  propertyNames: string[];
   readonly _type!: FromSchema<S>;
 
   constructor (definition: S, ajv: Ajv = AJV) {
     this.ajv = ajv;
     this.definition = definition as JSONSchema6;
-    this.propertyNames = Object.keys(this.definition.properties)
     this.validate = this.ajv.compile({
       $async: true,
       ...this.definition
     });
   }
 
+  get propertyNames () {
+    return Object.keys(this.definition.properties || {});
+  }
+
   extend <D extends JSONSchemaDefinition> (definition: D) {
     const def = definition as JSONSchema6;
     const extended = {
diff --git a/packages/schema/test/schema.test.ts b/packages/schema/test/schema.test.ts
index 710b8f5111..15a01d2029 100644
--- a/packages/schema/test/schema.test.ts
+++ b/packages/schema/test/schema.test.ts
@@ -205,4 +205,34 @@ describe('@feathersjs/schema/schema', () => {
       user: { email: 'hello@feathersjs.com', age: 42 }
     });
   });
+
+  it('works with oneOf properties (#2508)', async () => {
+    const oneOfSchema = schema({
+      $id: 'schemaA',
+      oneOf: [
+        {
+          type: 'object',
+          additionalProperties: false,
+          required: ['x'],
+          properties: {
+            x: { type:'number'}
+          }
+        },
+        {
+          type: 'object',
+          additionalProperties: false,
+          required: ['y'],
+          properties: {
+            y: { type:'number'}
+          }
+        }
+      ]
+    } as const);
+
+    const res = await oneOfSchema.validate({
+      x: '3'
+    });
+
+    assert.deepStrictEqual(res, { x: 3 });
+  });
 });