diff --git a/src/data-structures/stack/Stack.js b/src/data-structures/stack/Stack.js
index daa5d939..664df053 100644
--- a/src/data-structures/stack/Stack.js
+++ b/src/data-structures/stack/Stack.js
@@ -16,7 +16,7 @@ export default class Stack {
    * @return {*}
    */
   peek() {
-    if (!this.linkedList.tail) {
+    if (this.isEmpty()) {
       return null;
     }