Based on Rapid-Eye image data from 2010, DEM, soil type date and daily precipitation data from 6 national meteorological stations, Soil Conservation Service (SCS) model has been established to study rainwater resources potential and its temporal-spatial distribution characteristics in Dianchi Lake Basin. The results showed that: (1) The available rainwater resources potential were 0.2718, 0.5025, and 0.2333 billion cubic meters from 2009 to 2011 in Dianchi Lake Basin，currently，the rainwater resources can be collected and used mainly in the area of transportation and residential land，the average annual available potential of rainwater resources can be reached to 0.1874 billion cubic meters. (2) The interannual variation of rainwater resources is significantly affected by precipitation, and there was a positive correlation between them. The maximum value of rainwater resources occurs in July to August, while the minimum mainly occurs in February. (3) The current runoff production capacities of waters, transportation and residential land use types were stronger than that of paddy, and rainfall runoffs of the different land use types appeared in different times. (4) The high value areas of rainwater resources were mainly distributed in Dianchi and the main urban area on the north of Dianchi, while the low value areas were mainly distributed in eastern and southeastern Dianchi Lake basin.