The Blue Cave (traditional Chinese: 藍洞; simplified Chinese: 蓝洞; pinyin: Lán Dòng) is a cave on Xiji Islet in Wang'an Township, Penghu, Taiwan.

It is part of the South Penghu Marine National Park.

The cave was created by natural erosion.

[1] The cave is prone to rock falls due to sea erosion and uneven surfaces.

This article about a location in Taiwan is a stub.