Tongnan District (Tongnan County) is subordinate to Chongqing City and located in the northwest of Chongqing. It is the new industrial base of Chengdu-Chongqing, the ecological and cultural tourism destination of western Chongqing, the green vegetable capital of western China, the core part of Chengdu-Chongqing double-city economic circle, and the "bridgehead" city of the first batch of modern agricultural demonstration areas, the national health city and the main urban area of Chongqing. It is adjacent to Hechuan District and Tongliang District in the east, Dazu District in the south, Anyue County, Ziyang City, Sichuan Province, Anju District, Suining City, Sichuan Province, Chuanshan District, Suining City, Sichuan Province in the west, Pengxi County, Suining City, Sichuan Province and Wusheng County, Guang'an City, Sichuan Province in the north, and faces Jialing District, Nanchong City, Sichuan Province.

Tongnan District covers an area of 1583 square kilometers and has jurisdiction over 3 streets and 20 towns; By 2021, the permanent population of Tongnan District is 690400. In 2021, Tongnan District will achieve a GDP of 53.935 billion yuan, an increase of 9.5% over the previous year. Tongnan belongs to the shallow hilly landform of the basin, with flat terrain and an altitude of 300-450 meters; It is a subtropical humid monsoon climate with mild climate, rich heat, abundant rainfall, sufficient sunshine, and suitable for farming in four seasons.

Tongnan District was established as a county in 373 AD (the first year of Ningkang in the Eastern Jin Dynasty), and Dong'an County was established in 1912. In 1914, it was renamed Tongnan County because it was located in the south of Tongchuan Prefecture. In 1958, Tongnan belonged to Mianyang. In January 1976, Tongnan was transferred to Jiangjin. In 1997, Tongnan was under the jurisdiction of Chongqing municipality. On June 27, 2015, Tongnan was removed from the county and divided into districts, and the birth of the great men of the era such as Yang Menggong, Yang Shangkun, Yang Baibing, and the birth of historical and cultural celebrities such as Chen Tuan, Lv Daqi, and Liao Jingqiu.

There are many cultural attractions in Tongnan District, such as the Great Buddha Temple scenic spot, the ancient town of Shuangjiang, and the hometown of Chen Tuan. It has 4 national key cultural relics protection units and 10 Chongqing municipal cultural relics protection units. It is an important transportation hub in Sichuan-Chongqing region. There are Chongqing-Suinning Railway, Chongqing-Suinning Expressway, Tongrong Expressway and Hechuan-Anyue Expressway. National Highway 246, National Highway 319 and National Highway 351 pass through the border.