Fangchenggang (Chinese: 防城港 "Port of Fangcheng") is a prefecture-level city in the south of Guangxi Zhuang Autonomous Region, People's Republic of China.

Fangchenggang is the southernmost port in China and is located in Fangcheng. It primarily services bulk carriers, of up to 180,000 t (180,000 long tons; 200,000 short tons) deadweight tons in size. The closest airport is located in Van Don, about 91 km away (1 hour drive). As of December 2018, the region had large amounts of land reclamation in progress to build new and additional ports. The resident population of the city in 2024 will be 1,079,800.

The city was formerly called "Fangcheng Pan-Ethnicities Autonomous County" (December 25, 1978 – May 23, 1993).

Fangchenggang is a coastal city in southern Guangxi that borders Vietnam. Its area is 6,242.94 km² (2,410.41 sq mi), 120 km² (46 sq mi) of that urban.

Fangchenggang has two urban districts, one county, one county-level city, 17 townships, six towns, 283 villages, and seven subdistricts.

Districts:

County-level city:

County: