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Based on the remote sensing data of NOAA/AVHRR from 1991 to 2000 and the winter wheat yield data at the same period, the correlation equation between winter wheat yields and vegetable index of every pixel was established and hereby the winter wheat yield of every pixel was computed. According to the threshold values of the high, middle and low yield farmlands, the yield type of every pixel was determined. The distribution diagram of winter wheat yield types in Shandong was given by means of GIS. The formation causes of the middle and low farmlands were analyzed.