The bilateral relations between the Kingdom of Cambodia and the People's Republic of China have strengthened considerably after the end of the Cambodian-Vietnamese War, during which China had supported the Khmer Rouge against Vietnam.
Although they do not share a contiguous border, China has had a historic cultural and commercial relationship with Cambodia. Ethnic Chinese constitute approximately 3-5% of Cambodia's population or 350,000, and although they were discriminated against by the Khmer Rouge and the Vietnamese, they have re-emerged as a prominent business community. China has served Cambodia as a counterweight to the dominating influence of Vietnam. In the mid-20th century, Communist China supported the Maoist Khmer Rouge against Lon Nol's regime during the Cambodian Civil War and its subsequent take-over of Cambodia in 1975. Also, Mao Zedong had fostered good relations with Prince Norodom Sihanouk, who also fought against Lon Nol and backed the Khmer Rouge. When Vietnamese forces invaded Cambodia in 1978, China provided extensive political and military support for the Khmer Rouge. In 1979, Chinese forces waged a brief border war against Vietnam, partly to threaten Vietnam into pulling out of Cambodia. The Paris Peace Conference on Cambodia, July 1989 - October 1991, resolved Cambodia–China relations and contributed to re-integrating China into major power multilateral negotiations. After Vietnam's withdrawal from Cambodia and the U.N.-sponsored elections in 1993, China recognized and supported the new democratic government.
Since 1997, China began developing closer relations with the regime of Cambodian Prime Minister Hun Sen, who had actually been a pro-Vietnamese leader and a defector from the Khmer Rouge during Vietnam's occupation of Cambodia. Although initially backing Hun Sen's political opponent Prince Norodom Ranariddh and his FUNCINPEC, China was disenchanted with Ranaridh's efforts to build a closer relationship with Taiwan, which is claimed by China. Facing international isolation after the 1997 coup that brought him to power, Hun Sen cultivated close ties with China, which opposed efforts by Western countries to impose economic sanctions on Cambodia. China's close ties with Cambodia have also served to gain leverage against Vietnamese influence in the region. Cambodia has severed all links with Taiwan and has strongly supported the reunification of Taiwan with China.
During the visit of Chinese Premier Wen Jiabao between April 7-April 8, 2006 both nations signed several bilateral agreements and a treaty of "Comprehensive Partnership of Cooperation." China diversified its aid and investments in Cambodia and promised to provide USD 600 million in loans and grants. China has canceled much of Cambodia's debt and granted a fresh loan of USD 12.4 million for the construction of the building housing the Cambodian government's council of ministers and the restoration of the Angkor Wat temple and heritage site. About USD 200 million has been earmarked as a low-interest loan for the construction of bridges spanning the Mekong and Tonle Sap rivers. China has cultivated strong ties with Cambodia, gaining access to its sea ports that can allow China to exploit oil reserves in the Gulf of Tonkin. During the visit, Cambodian Prime Minister Hun Sen described China as Cambodia's "most trustworthy friend."
China has also cultivated military ties. In the aftermath of the 1997 coup, China provided USD 2.8 million in military aid and has since supplied wide range of military equipment, training of military and police cadre and naval vessels to combat drug trafficking and piracy. China has also funded Chinese language schools in Cambodia. Immigration of Chinese workers to Cambodia has also stepped up in recent years and is estimated between 50,000 to 300,000.
Trade between Cambodia and China totaled USD 732 million in 2006. However, Cambodia has a significant trade deficit of USD 632 million with China as 60% of products in Cambodian markets are Chinese-made. By 2004, 16.5% of Cambodia's imports, valued USD $527 million came from China, excluding almost 20% of imports coming from Hong Kong and worth USD 615 million. China's Sino-Hydropower Corporation began a USD 280 million project to construct a 193-megawatt Kamchay hydroelectric power station - reportedly the biggest foreign investment project in Cambodian history. China's government and businesses have invested in as many as 243 major projects worth USD 925 million in agriculture, mining, oil refineries, metals, automobiles, ports, garments and tourism. The China National Overseas Oil Corporation (CNOOC) have sought to launch projects for oil exploration and exploiting of Cambodia's hydrocarbon reserves.
China's dominant participation in Cambodia's economy, its close cultivation of ties with the Cambodian government and the influx of Chinese immigrants has raised concerns about an anti-Chinese backlash from Cambodians, many of whom resent China for its support of the Khmer Rouge, which conducted a genocide that claimed the lives of more than 1.7 million Cambodians. The Cambodian government's suppression of the Falun gong, a religious group banned by China, and extradition of 2 Falungong activists to China was criticized by human rights activities and the U.N. commission for refugees. China's influence is suspected to be shielding the pro-China Khmer Rouge leaders from standing trial for crimes against humanity. Suspected preferential treatment for Cambodia-based Chinese firms and the National Assembly of Cambodia's guarantee of profits for the Chinese investors in the Kamchay power plant has also provoked widespread criticism of China's growing political clout in Cambodia.
- Cardenal, Juan Pablo; Araújo, Heriberto (2011). La silenciosa conquista china. Barcelona: Crítica. pp. 230–232. (Spanish)
- Storey, Ian (April 2006). "China's tightening relationship with Cambodia" (– Scholar search). China Brief 6 (9). Retrieved 2008-06-17.[dead link][dead link]
- "China's growing influence in Cambodia". Asia Times. 2006-10-06. Retrieved 2008-06-17.
- "Vietnam - China". U.S. Library of Congress. Retrieved 2008-06-03.
- "China gives Cambodia $600m in aid". BBC News. 2006-04-08. Retrieved 2008-06-17.
- Hoa Kỳ ngưng viện trợ, Trung Quốc tặng ngay Phnom Penh 257 quân xa (Vietnamese)