diff --git a/number/gcd.rs b/number/gcd.rs
new file mode 100644
index 0000000..de751d2
--- /dev/null
+++ b/number/gcd.rs
@@ -0,0 +1,6 @@
+let gcd = |mut x: i64, mut y: i64|{
+    while y != 0 {
+        (x, y) = (y, x % y);
+    }
+    x
+};
\ No newline at end of file