diff --git a/src/leecode/javascript/80.删除有序数组中的重复项-ii.js b/src/leecode/javascript/80.删除有序数组中的重复项-ii.js
new file mode 100644
index 0000000..197ea63
--- /dev/null
+++ b/src/leecode/javascript/80.删除有序数组中的重复项-ii.js
@@ -0,0 +1,50 @@
+/*
+ * @lc app=leetcode.cn id=80 lang=javascript
+ *
+ * [80] 删除有序数组中的重复项 II
+ */
+
+// @lc code=start
+/**
+ * @param {number[]} nums
+ * @return {number}
+ */
+var removeDuplicates = function (nums) {
+  //重复次数
+  let repeat = 1;
+  //当前判定数
+  let cur = nums[0];
+  //当前移动到的位置
+  let index = 1;
+  //有效尾部
+  let tail = nums.length - 1;
+  for (; index < nums.length; index++) {
+    if (nums[index] < cur) {
+      index--;
+      break;
+    }
+    if (nums[index] == cur) {
+      repeat++;
+    } else {
+      repeat = 1;
+      cur = nums[index];
+    }
+    if (repeat >= 3) {
+      if (nums[tail] == cur) {
+        return index--;
+      }
+      let cursor = index + 1;
+      while (cursor <= tail) {
+        [nums[cursor - 1], nums[cursor]] = [nums[cursor], nums[cursor - 1]];
+        cursor++;
+      }
+      tail--;
+      index--;
+    }
+  }
+  return index + 1;
+};
+
+console.log(removeDuplicates([0, 0, 1, 1, 1, 1, 2, 3, 3]));
+
+// @lc code=end