The shortage of water resources is a key factor limiting the sustainable development of the economy and society in Beijing. This study analysed the spatiotemporal patterns of Beijing's water conservation services (WCS) based on the water balance equation at multiple scales, including city, main functional areas and key districts and counties, determined the differences in the water conservation amount among different land cover types and investigated the reasons for the spatiotemporal differences in the water conservation amount. The results indicated that: (1) compared to 2005, water conservation amount increased substantially in 2010. However, the overall water conservation capacity was low. (2) Among the various land cover types in Beijing, the average water conservation capacity decreased in the following order: wetland, forest, grassland, cropland, bare land and artificial surface. (3) The average water conservation amount in the main functional areas of Beijing varied substantially and was positive only in the ecological conservation area (ECA). (4) The water conservation capacity of each district and county varied substantially within ECA, among which the contribution of the forest in Miyun District, Huairou District and Pinggu District was the highest. The changes in the spatiotemporal patterns of Beijing's WCS were the synthetic effects of changes in the land covers and meteorological conditions. This study is helpful in achieving the sustainable utilization of water resources in Beijing.