diff --git a/problems/0110.平衡二叉树.md b/problems/0110.平衡二叉树.md
index c0914f05..9d43407a 100644
--- a/problems/0110.平衡二叉树.md
+++ b/problems/0110.平衡二叉树.md
@@ -730,5 +730,33 @@ bool isBalanced(struct TreeNode* root){
 }
 ```
 
+## Swift:
+
+>递归
+```swift
+func isBalanced(_ root: TreeNode?) -> Bool {
+    // -1 已经不是平衡二叉树
+    return getHeight(root) == -1 ? false : true
+}
+func getHeight(_ root: TreeNode?) -> Int {
+    guard let root = root else {
+        return 0
+    }
+    let leftHeight = getHeight(root.left)
+    if leftHeight == -1 {
+        return -1
+    }
+    let rightHeight = getHeight(root.right)
+    if rightHeight == -1 {
+        return -1
+    }
+    if abs(leftHeight - rightHeight) > 1 {
+        return -1
+    } else {
+        return 1 + max(leftHeight, rightHeight)
+    }
+}
+```
+
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 <div align="center"><img src=https://code-thinking.cdn.bcebos.com/pics/01二维码一.jpg width=500> </img></div>