diff --git a/javascript/217-Contains-Duplicate.js b/javascript/217-Contains-Duplicate.js
new file mode 100644
index 000000000..4f3bec692
--- /dev/null
+++ b/javascript/217-Contains-Duplicate.js
@@ -0,0 +1,13 @@
+class Solution {
+  containsDuplicate(nums) {
+    const hashset = new Set()
+    for (let num of nums) {
+      if (hashset.has(num)) {
+        return true
+      } else {
+        hashset.add(num)
+      }
+    }
+    return false
+  };
+}
\ No newline at end of file