diff --git a/Math/Problems/Javascript/factorial.js b/Math/Problems/Javascript/factorial.js
new file mode 100644
index 0000000..cb53c9d
--- /dev/null
+++ b/Math/Problems/Javascript/factorial.js
@@ -0,0 +1,9 @@
+function factorial(num) {
+  if (num < 0) 
+        return -1;
+  else if (num == 0) 
+      return 1;
+  else {
+      return (num * factorial(num - 1));
+  }
+}