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In arid oases irrigation areas, soil secondary salination is one of the main problems leading to land desertification, so as to imperil the soil quality, growing of crops and agricultural production, even leading to abandonment of agricultural soils. Most salinization processes of salt accumulation in irrigated lands are largely determined by the salinity of the irrigation water and the groundwater level in the areas. So it is very crucial to control groundwater and irrigation amount for agricultural development. In order to find out the optimal irrigation amount and reasonable groundwater depth in typical cultivated land in Hetao Irrigation District, field trials were conducted for two consecutive years in 2017 and 2018, and sunflower farmland was selected as the research object, saturatedunsaturated soil moisture and solute motion theory was applied, and HYDRUS-2D numerical model was utilized for numerical simulation of water and salt transport in GSPAC system under different irrigation and groundwater depth conditions in the study area, and analysis of water and salt transport conditions under different irrigation conditions was made to determine the optimal irrigation system and reasonable groundwater depth. The simulation results were compared with the field test results, and the model simulation values were in good agreement with the measured values. The results showed that the optimal irrigation amount in the test area was 82.8~85.5mm, and the reasonable grounding depth of groundwater was 160.72cm. The research can provide a theory basis for rational utilization of water resources and watersalt regulation in arid regions.