diff --git a/src/components/modal/modal.vue b/src/components/modal/modal.vue
index 0ace491..51a529b 100644
--- a/src/components/modal/modal.vue
+++ b/src/components/modal/modal.vue
@@ -132,7 +132,8 @@
             },
             handleWrapClick (event) {
                 // use indexOf,do not use === ,because ivu-modal-wrap can have other custom className
-                if (event.target.getAttribute('class').indexOf(`${prefixCls}-wrap`) > -1) this.mask();
+                const className = event.target.getAttribute('class');
+                if (className && className.indexOf(`${prefixCls}-wrap`) > -1) this.mask();
             },
             cancel () {
                 this.close();
--
libgit2 0.21.4