The research on mechanism and adaptive characteristics of grassland ecosystem biomass with increased precipitation and nitrogen deposition is helpful to understand the impact of climate change on productivity and service function of grassland ecosystem,which has great significance to the sustainable development of grassland ecosystem.This paper reviewed the possible change mechanism of grassland biomass under increasing precipitation and nitrogen deposition,and discussed the changes of plant adaptation to environment. On this basis,the challenges and main problems in the current research of grassland ecosystem under climate change were proposed.