The Sihcao Wetlands (Chinese: 四草; Hanyu Pinyin: Sìcǎo; Tongyong Pinyin: Sìhcǎo; Wade–Giles: Ssu4-ts'ao3) are wetlands in Annan District, Tainan, Taiwan.

They were set aside in 1994 by the Tainan City Government and consist of approximately 515 hectares (1,270 acres).

[1] The protected area in Taiwan consists of mangrove swamps, salt marshes, rivers, canals, and drainage ditches.

In November 2004, the Sihcao Wildlife Refuge (四草野生動物保護區) was created to further protect the area, especially from possible encroachment from the nearby Tainan Technology Industrial Park.

[2] In 2009, the Sihcao Wetlands became part of the Taijiang National Park.