Tongjiang County (Chinese: 通江县; pinyin: Tōngjiāng Xiàn) is a county in the northeast of Sichuan Province, China, bordering Shaanxi Province to the north.

It is under the administration of the prefecture-level city of Bazhong, with an area of 4,125 km2 (1,593 sq mi), and a population of approximately 522,000 in 2020.

Tongjiang has resources of natural gas, marble, dolomite, gypsum and uranium.

Provincial Highways 201 and 302 are main roads through Tongjiang County.

Tongjiang is also known for its local specialty of cooked Fungus, and is known colloquially as the “中国银耳之乡” or "Hometown of Chinese White Fungus", and is listed for national protection as the originating region of this product; much like Champagne is in France.