diff --git a/problems/0141.环形链表.md b/problems/0141.环形链表.md
index 34b8d25f..14c21b67 100644
--- a/problems/0141.环形链表.md
+++ b/problems/0141.环形链表.md
@@ -114,6 +114,17 @@ class Solution:
 ## JavaScript
 
 ```js
+var hasCycle = function(head) {
+    let fast = head;
+    let slow = head;
+    // 空链表、单节点链表一定不会有环
+    while(fast != null && fast.next != null){
+        fast = fast.next.next; // 快指针，一次移动两步
+        slow = slow.next; // 慢指针，一次移动一步
+        if(fast === slow) return true; // 快慢指针相遇，表明有环
+    }
+    return false; // 正常走到链表末尾，表明没有环
+};
 ```
 
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