Tongshan (simplified Chinese: 通山县; traditional Chinese: 通山縣; pinyin: Tōngshān Xiàn) is a county of Xianning City, in the southeastern part of Hubei province, People's Republic of China, bordering Jiangxi to the south.

The county is located along Hubei's mountainous south-eastern border with Jiangxi.

The county is roughly coterminous with the upper part of the basin of the Fushui River, which flows eastward, into the neighboring Yangxin County, where it discharges into the Yangtze.

The county seat is in the town of Tongyang (通羊镇); as it is customary in China, this location is usually labeled on less-detailed maps simply as "Tongshan County" (通山县) or "Tongshan".

Xianning Nuclear Power Plant is under construction near Tongshan County's Dafan Town.