Abstract: The research indicated that the total aboveground biomass and the yield of various nutritive substances of the population of Astragalus adsurgens were featured in the single kurtosis during growing period. The fourth-order polynemial could be used to discribe and predict the yield in every period. The peak values for various organ biomass and the yield of nutritive substances were different The aboveground biomass reached the highest in early Sept. of florescence, of which the highest stem biomass occurred after florescence and the highest leaf biomass before it. The highest content of crude protein and crude fat appeared before the formation of highest biomass being 166g.m-2 and 29g·m-2 respectively. The peak for crude fiber and N-free extract appeared after biomass peak being591g.m-2 and 663g.m-2 respectively. The biomass formation of the herbage was a process in which soil moisture was of deficit gradually. There was obviously a negative correlation between the aboveground biomass and soil water storage in root zone (3m) during the period from turning green to peak biomass. The CGR was a single kurtosis, with its maximum occurred in early July (14.9g.m-2·day) . The NAR had a short increasing period but RGR continuously went down. The nutrition content and their accumulation rates were markedly different in various organs during growing period.