In this paper, by analysing some basic factors the authors point out that some main climatological factors, such as light, temperature and mois ture, obviously affect the yields of crops, and then propose a agroclimatic model for the output of five crops as to evaluate regional agroclimatic resources. Under conditions of the present climate, the three correct coefficients in this model, interception of leaf area for light, temperature and moisture, are given. On the premise of analysing the climatological yields of crops and their variances, in order to develop the advantages of climate, the main regions of croping are drawn out. After calculating adjustment coefficients for planting area of five varieties of Crops in 45 counties, the authors plot the composite distribution map of crops.