diff --git a/changelog.md b/changelog.md
index 5f8e085be6..b3ccc306ba 100644
--- a/changelog.md
+++ b/changelog.md
@@ -1,5 +1,6 @@
 # 更新日志
 2.0(2020-12)
+- 文件上传控件新增API(setMaxFileLength)以动态设置最大上传文件数量
 - Pane系列提供small和big两种大小的加载动画
 - 同步树列表系列支持不显示节点连接线和展开收起图标
 - 规范了下拉树trigger中显示值的显示顺序
diff --git a/src/base/single/editor/editor.multifile.js b/src/base/single/editor/editor.multifile.js
index 3a8db85ae4..f9577f3739 100644
--- a/src/base/single/editor/editor.multifile.js
+++ b/src/base/single/editor/editor.multifile.js
@@ -71,6 +71,10 @@ BI.MultifileEditor = BI.inherit(BI.Widget, {
         this.file.reset();
     },
 
+    setMaxFileLength: function (v) {
+        this.file.setMaxFileLength(v);
+    },
+
     select: function () {
         this.file.select();
     },
diff --git a/src/base/single/input/file.js b/src/base/single/input/file.js
index 98918bd3d7..ea5024e9be 100644
--- a/src/base/single/input/file.js
+++ b/src/base/single/input/file.js
@@ -545,12 +545,12 @@
         },
 
         _events: function (wrap) {
-            var self = this;
+            var self = this, o = this.options;
             event.add(wrap.dom.input, "change", function () {
                 event.del(wrap.dom.input, "change", arguments.callee);
                 var input = wrap.dom.input.cloneNode(true);
                 var files = F(wrap.dom.input);
-                if (wrap.maxLength !== -1 && wrap.maxLength < files.length) {
+                if (o.maxLength !== -1 && o.maxLength < files.length) {
                     self.fireEvent(BI.File.EVENT_ERROR, {
                         errorType: 2
                     });
@@ -654,6 +654,13 @@
             });
         },
 
+        setMaxFileLength: function(v) {
+            this.options.maxLength = v;
+            if (this.wrap) {
+                this.wrap.maxLength = v;
+            }
+        },
+
         select: function () {
             this.wrap && BI.Widget._renderEngine.createElement(this.wrap.dom.input).click();
         },