Koh Kong (Khmer: ខេត្តកោះកុង IPA: [kÉ‘h koÅ‹]) is a province (khaet) of Cambodia. The name means "Kŏng Island Province". Its capital is Koh Kong.

The most south-western province of Cambodia, Koh Kong has a long undeveloped coastline and a mountainous, forested and largely inaccessible interior which embraces part of the Cardamom Mountains and a section of Kirirom National Park. Its tourist attractions include casinos and waterfalls, while an Export Processing Zone and new port facilities are being developed for trade.

After Cambodia’s liberation from the Khmer Rouge in 1979, Koh Kong was still quite unpopulated. After national government policy encouraged people to live in Koh Kong, there has been a net influx of people. It is estimated that the average annual growth rate in Koh Kong is 16 per cent, which has put pressure on the mangrove resources in the province. Koh Kong's towns have developed rapidly partially in response to market pressures from Thailand and because of in-migration from other parts of Cambodia

The province is an increasingly popular gateway to Cambodia from Hat Lek in eastern Thailand, in part due to the reasonably direct access to the port and beach resort town of Sihanoukville. The border is located at Cham Yeam, about 14km from Koh Kong.

Traveling to Koh Kong has become an enjoyable journey, where bridges were built, the first stage in 2002. A landmark of Koh Kong was made possible by L.Y.P. Group, the longest ever built bridge in Cambodia where you would want to experience the 1,900-meter crossing the sea connecting provincial town of Koh Kong to Koh Kong Resort and the international check point. In 2007 a new sealed road (National Route 48) was completed from the town to Sre Ambel on the Phnom Penh to Sihanoukville highway, including the 4 remaining river crossings where bridges were opened in May 2008 which are donations by the Thai government to Cambodia.