diff --git a/src/index.ts b/src/index.ts
index 3e8f11b..532bdda 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -16,15 +16,7 @@ import type {
   Values,
 } from './interface';
 import { messages as defaultMessages, newMessages } from './messages';
-import {
-  asyncMap,
-  complementError,
-  convertFieldsError,
-  deepMerge,
-  format,
-  isEmptyValue,
-  warning,
-} from './util';
+import { asyncMap, complementError, convertFieldsError, deepMerge, format, warning } from './util';
 import validators from './validator/index';
 
 export * from './interface';
@@ -154,9 +146,8 @@ class Schema {
             source = { ...source };
           }
           value = source[z] = rule.transform(value);
-          const type = rule.type || ((Array.isArray(value) ? 'array' : typeof value) as RuleType);
-          if (!isEmptyValue(value, type)) {
-            rule.type = type;
+          if (value !== undefined && value !== null) {
+            rule.type = rule.type || ((Array.isArray(value) ? 'array' : typeof value) as RuleType);
           }
         }
         if (typeof rule === 'function') {
diff --git a/tests/number.spec.ts b/tests/number.spec.ts
index db1c3cb..fbb54e4 100644
--- a/tests/number.spec.ts
+++ b/tests/number.spec.ts
@@ -167,6 +167,17 @@ describe('number', () => {
       v: { required: true, transform: v => undefined },
     }).validate(value, errors => {
       expect(errors).toBeTruthy();
+      expect(errors[0].message).toBe('v is required');
+      done();
+    });
+  });
+  it('empty array message is "v is required"', done => {
+    const value = { v: [] };
+    new Schema({
+      v: { required: true, transform: () => [] },
+    }).validate(value, errors => {
+      expect(errors).toBeTruthy();
+      expect(errors[0].message).toBe('v is required');
       done();
     });
   });