Beihai, often called Bakhoi, is a prefecture-level city of Guangxi, China. Beihai means "north sea", meaning that the place is a seaport on the north shore of the Gulf of Tonkin. Beihai has a large shipyard and is reputed to still be a pirate habour. Beihai is known within China as a travel destination. While Beihai does suffer from pollution as much of China does, it isn't nearly as severe as most other parts of the country.

The city of beihai is located at the southern end of Guangxi and on the northeastern bank of Beibu Gulf. Beihai is only 206 kilometres away from Nanning in the northwest, 198 kilometres away from Zhanjiang city in the east and 147 nautical miles from Haikou city in the southeast. The sea on the south, north and west side, surrounds the whole city. It has two islands, Weizhou (24.74square kilometres) and Xieyang (1.8 square kilometres). Weizhou is about 20.2 nautical miles away from the city.

Beihai enjoys a good geographical location. Backed by the great southwest regions (Yunnan, Guizhou, Sicuan provinces) of China, facing Hainan province across the sea, it is the centre of the great southwest regions, Hainan and the Southeast Asia, with cities of the Southeast Asia close by. It covers a total area of 3,337 square kilometres, of which the city proper accounts for 957 square kilometres.