Lake Tai (Chinese: 太湖; pinyin: Tài Hú; literally "Grand Lake") is a large lake in the Yangtze Delta plain. The waters of the lake belong to the former in its entirety with part of its southern shore forming the boundary between the two provinces. With an area of 2,250 km² and an average depth of 2 metres, it is the third largest freshwater lake in China, after the Poyang and Dongting Lakes. The lake houses about 90 islands, ranging in size from a few square meters to several square miles.

The lake is renowned for its unique limestone formations. These Chinese scholar's rocks are often prized as a decorating material for the traditional Chinese garden, especially in areas such as Suzhou.

According to many guidebooks, Lake Tai is best seen from the scenic viewpoint in Xihui Park in the west of Wuxi, from the top of Dragon Light Pagoda, from which both Wuxi and Lake Tai are visible. Another wellknown panoramic view is from Longshan (Mt Long), where famous ancient poet Su Shi once wrote a poem.

Three of the lake's islands are known as the Sanshan Islands ('three hill islands'), one of the Chinese National Geological Parks.

When late spring and early summer come, the vast area of rapeseed will impress you if you pass by the banks of Taihu Lake. Taihu Lake is a pearl in South China and obtains quite a lot relics and historical places of interest.