diff --git a/source/chapter2/04_Collection_Types.md b/source/chapter2/04_Collection_Types.md
index 7fdf8c8d..718cfb1c 100755
--- a/source/chapter2/04_Collection_Types.md
+++ b/source/chapter2/04_Collection_Types.md
@@ -7,7 +7,7 @@
 本页包含内容：
 
 - [数组（Arrays）](#arrays)
-- [集合 (Sets)](#sets)
+- [集合（Sets）](#sets)
 - [字典（Dictionaries）](#dictionaries)
 - [集合的可变性（Mutability of Collections）](#mutability_of_collections)