diff --git a/problems/0404.左叶子之和.md b/problems/0404.左叶子之和.md
index e5daa9db..e6a6682b 100644
--- a/problems/0404.左叶子之和.md
+++ b/problems/0404.左叶子之和.md
@@ -226,6 +226,71 @@ class Solution:
 ```
 Go：
 
+> 递归法
+
+```go
+/**
+ * Definition for a binary tree node.
+ * type TreeNode struct {
+ *     Val int
+ *     Left *TreeNode
+ *     Right *TreeNode
+ * }
+ */
+func sumOfLeftLeaves(root *TreeNode) int {
+    var  res int
+    findLeft(root,&res)
+    return res
+}
+func findLeft(root *TreeNode,res *int){
+    //左节点
+    if root.Left!=nil&&root.Left.Left==nil&&root.Left.Right==nil{
+        *res=*res+root.Left.Val
+    }
+    if root.Left!=nil{
+        findLeft(root.Left,res)
+    }
+    if root.Right!=nil{
+        findLeft(root.Right,res)
+    }
+}
+```
+
+> 迭代法
+
+```go
+/**
+ * Definition for a binary tree node.
+ * type TreeNode struct {
+ *     Val int
+ *     Left *TreeNode
+ *     Right *TreeNode
+ * }
+ */
+func sumOfLeftLeaves(root *TreeNode) int {
+    var  res int
+    queue:=list.New()
+    queue.PushBack(root)
+    for queue.Len()>0{
+        length:=queue.Len()
+        for i:=0;i<length;i++{
+            node:=queue.Remove(queue.Front()).(*TreeNode)
+            if node.Left!=nil&&node.Left.Left==nil&&node.Left.Right==nil{
+                res=res+node.Left.Val
+            }
+            if node.Left!=nil{
+                queue.PushBack(node.Left)
+            }
+            if node.Right!=nil{
+                queue.PushBack(node.Right)
+            }
+        }
+    }
+    return res
+}
+```
+
+
 JavaScript:
 递归版本
 ```javascript