Abandoning some reservoirs in the plain region of Xinjiang becomes possible as they undertake no task any more after the operation of mountain reservoirs. With the Jiahezi Reservoir in Manasi River Irrigation Area in Xinjiang as a case study, we investigate the feasibility of abandoning Jiahezi reservoir and the influence of abandonment on planting industry and reservoir group scheduling by analyzing the changes in planting industry in the irrigation area and schemes of reservoir scheduling before and after the abandonment of the Jiahezi Reservoir. Results show that abandoning Jiahezi Reservoir would reduce annual evaporation loss (by 980.9×10⁴~1884.0×10⁴m³) and leakage loss (by 135.7×10⁴~878.2×10⁴m³) of the reservoir group; improve the water quantity abandoned by the reservoir group (by 3474.4×10⁴ and 1 360.1×10⁴m³ respectively) in high and normal flow years but reduce (by 2 140.1×10⁴m³) in low flow years; significantly improve the output value of planting industry (by 30.8%~43.9%) and the cultivated area (by 17.4%~29.9%). Therefore, we conclude that the Jiahezi Reservoir can be abandoned after the operation of mountain reservoirs. Some other plain reservoirs of shallow water depth, small storage capacities and unsafe status in other similar areas in Xinjiang can also be abandoned.