Gunsan (Korean pronunciation: [kun.san]) is a city in North Jeolla Province, South Korea. It is on the south bank of the Geum River just upstream from its exit into the Yellow Sea. It has emerged as a high-tech manufacturing industrial city and an international trade seaport that is approximately 200 km (120 mi) southwest of Seoul on the midwest coast of the Korean Peninsula.

Gunsan’s economy thrives on fishing, agriculture and heavy industry west of the city in the reclaimed area known as the Industrial Zone. GM Korea operates a factory here that assembles the Chevrolet Aveo worldwide and as the Holden Barina in Australia and New Zealand. Near the port, the Tata Daewoo Commercial Vehicle factory produces Daewoo trucks for the domestic and export markets. In the domestic market vehicles are sold under Daewoo brand; the Tata brand name is used for export due to the dilution of the Daewoo brand.

It is a major port, especially for rice shipments, and is a commercial center for the rice grown in the Geum basin. Rice processing and shipbuilding are important industries, and paper, lumber, rubber, and plastic are also produced. Originally a poor fishing village, Gunsan gained importance with the development of its port, which was opened to foreign trade in 1899. The Japanese, who ruled Korea from 1905 to 1945, further developed the city and port.

Just south of Gunsan is the newly opened Saemangum Seawall, the longest dyke in the world.

Kunsan Air Base operated by the United States Air Force is in the city. To encourage investment, a free trade zone has been declared in the area.

Famous people from Gunsan include actress Lee Eun-ju, comedian Park Myeong-su, and Teen Top member L.Joe.