Tianjin, also Tientsin and T'ien-chin, China, the nation's third largest city. It lies on the Hai He at its junction with the Grand Canal, 31 miles (50 km) east of the Bo Hai, an arm of the Yellow Sea. Tianjin is an independent municipality, or shih, under the central government.

Tianjin is a major industrial, commercial, and transportation center. Articles manufactured here include textiles, chemicals, and processed foods. Metallurgical industries and the making of heavy machinery are also important. Tianjin handles much of the trade of the North China Plain. It is a leading port, reached by oceangoing as well as river vessels, and a major rail terminal on one of the principal routes to Manchuria. Tianjin and Nankai universities are in the city.

The site of the present city was settled during the Sung dynasty (960–1279). British and French troops occupied Tianjin in 1858 and 1860, when it became a treaty port (a port open to foreign residence and trade). The city was besieged by antiforeign Chinese during the Boxer Rebellion in 1900 and again occupied for a short time by British and French troops. The Japanese occupied Tianjin during 1937–45.

Population: Tianjin proper 9,156,000; the municipality, 9,848,731.