Dianjiang County (simplified Chinese: 垫江县; traditional Chinese: 墊江縣; pinyin: Diànjiāng Xiàn) is a county in the northeast of Chongqing Municipality, China, bordering Sichuan province to the northwest. As of 2015, it has two subdistricts, two townships, and 22 towns under its administration.

Dianjiang County was developed in the time of the Western Wei Emperor Gong Di in 555 CE. Before the Chongqing area became a municipality, Dianjiang belonged to other regions. From October 1, 1949, to March 14, 1997, it belonged to Dazhu, Fuling prefecture.

Dianjiang has two subdistricts, two townships, five regional center towns and 17 general towns.

Based on statistics from October 2015, in the first three quarters, Dianjiang County achieved a GDP of 16.63 billion yuan (an increase of 11.4 percent, and faster than the growth in the previous six months by 0.4 percentage points). The contributions to the GDP were composed of the primary sector producing 2.17 billion yuan (an increase of 4.5%); the secondary sector producing 8.78 billion yuan (an increase of 12.6%); and the tertiary sector producing 5.68 billion yuan (an increase of 12.2%).

The area is served by Dianjiang railway station on the Chongqing–Wanzhou intercity railway.