@@ -0,0 +1,33 @@
+module.exports = function MergeSort(nums) {
+    if(nums === null || nums.length <= 1) return;
+    MergeSortPart(nums, 0, nums.length-1);
+}
+
+function MergeSortPart(nums, l, r) {
+    if(l === r) {
+        return;
+    }
+    var mid = l + parseInt((r - l) / 2);
+    MergeSortPart(nums, l, mid);
+    MergeSortPart(nums, mid + 1, r);
+    Merge(nums, l, mid, r); 
+}
+
+function Merge(nums, l, mid, r) {
+    var help = new Array(r - l + 1);
+    var i = 0;
+    var p1 = l;
+    var p2 = mid + 1;
+    while(p1 <= mid && p2 <= r) {
+        help[i++] = nums[p1] > nums[p2] ? nums[p2++] : nums[p1++];
+    }
+    while(p1 <= mid) {
+        help[i++] = nums[p1++];
+    }
+    while(p2 <= r) {
+        help[i++] = nums[p2++];
+    }
+    for(i = 0; i < help.length; i++) {
+        nums[l+i] = help[i];
+    }
+}
@@ -3,6 +3,7 @@ var InsertSort = require('./InsertSort');
 var SelectSort = require('./SelectSort');
 var HeapSort = require('./HeapSort');
 var QuickSort = require('./QuickSort');
+var MergeSort = require('./MergeSort');
 
 function generateRandomAray(maxSize, maxValue) {
     var n = parseInt((maxSize+1)*Math.random());
@@ -55,7 +56,8 @@ for(var i = 0; i < testTime; i++) {
     // InsertSort(arr1);
     // SelectSort(arr1);
     // HeapSort(arr1);
-    QuickSort(arr1);
+    // QuickSort(arr1);
+    MergeSort(arr1);
     comparator(arr2);
     if(!isEqual(arr1, arr2)) {
         succeed = false;