With increasing urbanization and agricultural expansion, there is rapid loss, conversion, and degradation of global wetlands. Quantifying the key ecosystem services and elucidating the main providers of wetland can help implement sustainable and diverse wetland utilization strategies. This study estimates the economic values and dominant contributors of five key ecosystem services (i.e. flood regulation, water provision, water purification, cooling effect and habit maintenance) of wetlands in Beijing using the economic valuation methods with the wetland inventory data in 2014. There are 5.14*10~4 hm~2 wetlands in Beijing, 46% of which are natural wetlands and mainly distribute in outer suburban districts of Beijing, such as Miyun, Fangshan and Mentougou. These wetlands can annually regulate 20.75*10~8 m~3 of flood, supply 9.44*10~8 m~3 of water, purify 4.22*10~4 t of COD from surface water, absorb 3.03 PJ of heat by evaporation, and maintain 0.96*10~4 hm~2 super- quality habit. The economic values of the 5 key ecosystem services are 1.59*10~(10), 1.18*10~9, 1.69*10~8, 4.21*10~8 and 1.08*10~9 yuan, respectively. In addition, the reservoirs and rivers in Miyun, Yanqing, Fangshan, Huairou and Mentougou provide 78% of wetland ecosystem services, whereas the urban wetland resources in Xicheng, Dongcheng, Shijingshan, Chaoyang and Haidian also take important roles. The study highlights the economic values and the dominate contributors of wetland ecosystem services in Beijing, and provides basis for wetland protection policy when developing new urban areas.