The Xiyu Western Fort (Chinese: 西嶼西臺; pinyin: Xīyǔ Xītái) or Xiyu Western Battery (西嶼西砲臺 Xīyǔ Xī Pàotái,[1] informally 西台古堡 Xītái Gǔbǎo) is a former fort and battery in Wai'an Village, Xiyu Township, Penghu, Taiwan.

[2] In the 17th century, Chinese Ming Dynasty loyalist general Chen Guoxuan (陳國軒) built 15 batteries in Penghu to guard against Qing dynasty admiral Shi Lang.

Many of the batteries were destroyed during the Sino-French War of 1884 and 1885, when Penghu was one of the main theaters of conflict.

[1] It was designated a class-one historic relic in 1983 and, after a four-year renovation, was opened to the public in 1990.

The Penghu County government purchased three British-made Armstrong guns for the fort in 2008 for NT$20 million and they were installed in 2011.