Abstract: On the basis of the theory of crop growth simulation,the characters of a natural multi-population alpine meadow community were thoroughly studied in this paper,and a model was established,which can reflect the comprehensive influence of meteorological variables and biological factors on population biomass dynamics of the alpine meadow community.The main model set includes the layer by layer by layer quantitative simulation of the fundamental physiological processes such as photosynthesis,respiration,distribution and transfer of the assimilative products between aboveground and belowground,the simulation of dynamic development of LAI and community composition.The main model includes 6 submodels. All those models could well describe the dynamic changes of aboveground and belowground biomass of the alpine meadow community with season by testing.