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Net primary productivity ( N _ pp ) is one of useful indexes in global change studies. Utilization of remote sensing data from meteorological satellites is an objective way to estimate N _ pp . Using the processed annual normalization vegetation index, N _ pp values can be estimated from an experimental model (NPP-RS). The relationship between each crop's N _ pp and yields was then determined. The total yields can be assessed by the N _ pp value. The total yields and the yields of main crops from 1995 to 2000 in Jilin Province were estimated. The mean relative error is 13.6% for total yields, and 17.6% and 6.7% for maize and rice, respectively.