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Abstract. Prevailing groundwater conditions in High Plains have necessitated the adaption of water conservation technics to achieve sustainable agriculture in the region. The crop models could be convenient tools for adapting proper irrigation scheduling if they are properly evaluated. The well-known FAO AquaCrop model was calibrated and validated for simulating forage sorghum yield response to different deficit irrigation levels under a linear move irrigation system. Six irrigation treatments indicating 100 %, 80%, 70%, 50%, 40%, and 0% of full irrigation were done in a randomized pattern in 2014 and 2015 in southwest Kansas. The AquaCrop model was calibrated based on fully irrigation treatment in 2014. The accuracy of the model for calibration (2014 observations) was analyzed based on RMSE, NRMSE, R², d, and MBE indices which were 0.90 ton/ha, 0.11, 0.71, 0.89, and -0.4621 ton/ha for total biomass and 0.48 ton/ha, 0.22, 0.75, 0.76, and -0.30 ton/ha for grain yield, respectively. For model validation purpose (2015 observations), the values of RMSE, NRMSE, R², d and MBE indices were 0.61 ton/ha, 0.048, 0.90, 0.94, and -0.420 ton/ha for total biomass and 0.44 ton/ha, 0.17, 0.31, 0.54, and 0.37 ton/ha for grain yield, respectively. In addition, the good performance of the model was observed for simulating soil water content under sorghum cultivation and deficit irrigation applications, however, the adequacy of the model was not satisfactory. By considering the results of this study, it was revealed that the AquaCrop model performance was good to simulate yield and yield components of the forage sorghum under full and deficit irrigation conditions in western Kansas.