Abstract: To determine the assessement method of growth condition in different growth periods and yield of spring maize in the west the Liaoning province,based on weather,maize phenology,biomass and yield data from different sowing date experiment in Jinzhou from 2011 to 2015,the relationships between above-ground biomass of maize (AGB) in different growth periods,meteorological yield (MY) and actual evapotranspiration (AET) were investigated with Penman-Monteith and mathematical statistics methods.At the same time,a model evaluating growth conditions of different growth stages and final output of maize was established.The results show that linear relationships between AGB,MY and AET are significant,respectively.More specifically,the relationships between AGB in different growth periods and corresponding AET are significant at 5% level in sowing to seven-leaf stage and at 1% level in sowing to jointing,sowing to tasseling and sowing to milk stage.The forecast accuracies of the developed model for different maize growth periods range from 77.8% to 94.5%.In addition,the floor levels of water supplies for maize normally growing in the west of Liaoning province are 333.2 mm,23.3 mm,83.4 mm,118.9 mm and 57.7 mm during the whole growth period,sowing to seven leaf,seven leaf to jointing,jointing to tasseling and tasseling to milk stages,respectively.Meanwhile,for the stages when maize suffers drought stress,the influence of drought stress on yield in an order of heavy to light ranges at jointing-tasseling,tasseling-milky ripening,seven leaf-jointing,sowing-seven leaf and milk-maturation stage.In general,the method established in this paper can meet the demand on agrometerological yield forecast service and has realistic value in drought impact assessment operation.