Data of precipitation and aboveground biomass in sampling plots of 500 m×500 m were obtained from the Inner Mongolia Grassland Ecosystem Research Station of the Chinese Academy of Sciences, located at 43°32′20″N ～ 43°32′40″N,116°33′00″E ～ 116°33′30″E. From this database, we analyzed the relationship between aboveground biomass and precipitation, either annually, monthly, from April-June, June-August, or January-July, using correlation of SPSS software. In addition, differences between the aboveground biomas