Abstract: To select and evaluate the summer maize evapotranspiration model for drip irrigation in southern Xinjiang. Based on the dual-crop coefficient method, this study combined with the experimental data of mulched and unmulched drip irrigation summer maize in Aksu region of southern Xinjiang in 2022 and 2023, and evaluated the applicability of SIMDual Kc model. Four irrigation gradients were set under the conditions of mulched and unmulched drip irrigation. Based on stable carbon isotope technology, water balance method and actual observation data, the model parameters were calibrated. The model of SIMDual Kc was suitable for constructing to estimate summer maize evapotranspiration, soil evaporation and transpiration with mulched and unmulched drip irrigation. The estimated evapotranspiration, soil evaporation and crop transpiration were verified respectively.The results show that: SIMDual Kc model can estimate the evapotranspiration of summer maize with drip irrigation in southern Xinjiang. The measured values are in good agreement with the simulated values. The coefficient of determination between the simulated values and the measured values of evapotranspiration, evaporation and transpiration of summer maize with drip irrigation in mulched and unmulched land is 0.66～0.95, and the regression coefficient is 0.86～1.14. The consistency index ranges from 0.69 to 0.99, the root-mean-square error ranges from 0.14 to 19.41 mm, and the normalized root-mean-square error ranges from 9.63% to 28.32%. The parameters of SIMDual Kc model applicable to summer maize with mulched drip irrigation in the study area were 0.15 in the initial stage(crop coefficient), 1.2 in the middle stage(crop coefficient), 0.5 in the later stage(crop coefficient), 10 mm in depth of evaporation layer, 24 mm in total evaporation water, and 9 mm in easy evaporation water. The parameters of SIMDual Kc model applicable to summer maize with unmulched drip irrigation in the study area were 0.15 in the initial stage(crop coefficient), 1.15 in the middle stage(crop coefficient), 0.45 in the later stage(crop coefficient), 10 mm in depth of evaporation layer, 22 mm in total evaporation water, and 9 mm in easy evaporation water. The study can provide theoretical basis for the optimization of summer maize irrigation system in southern Xinjiang.