Gulangyu Island (鼓浪嶼 Pinyin: Gǔlǎng Yǔ) is a 1.78-km² carfree island off the coast of Xiamen, southern China.

As a place of residence for Westerners during Xiamen's colonial past, it is famous for its architecture and hosting China's only piano museum, giving it the nickname of "Piano Island" or "The Town of Pianos" (鋼琴之鄉) or "The Island of Music" (音樂之島). There are over 200 pianos on this island.

In addition, there is a museum dedicated to Koxinga, Haidishi Jie (海底世界) Marine World, a subtropical garden containing plants introduced by overseas Chinese, as well as Xiamen Museum, formerly the Eight Diagrams Tower (八卦樓).

In October 1945, Gulangyu became one of the first four districts of Xiamen City. However, in May 2003, Gulangyu District was absorbed into the larger Siming District (based on main Xiamen island).

The Chinese name also has musical roots, as gu lang means drum waves so-called because of the sound generated by the ocean waves hitting the reefs. Yu means "islet".

Gulangyu Island (foreground) has retained its traditional
architecture compared to Xiamen (background)