Improving food production and water use efficiency (WUE) in arid regions is essential to achieving sustainable agricultural development. Using agricultural data from Ili Prefecture spanning the years 2000–2020, this study systematically analyses the spatiotemporal variations in regional water resources and the challenges facing dryland agriculture. Based on these findings, a "Drip Irrigation to the Hills" engineering model was proposed to enable the precise distribution of water resources in sloped dryland areas, aiming to enhance irrigation efficiency and support sustainable agricultural development. This model enables effectively converting sloping land into productive arable farmland, increasing crop yields from 0.675 × 10⁸ kg to 1.0 × 10⁸ kg. A multi-objective optimization of the cropping structure, considering economic benefits, WUE, and energy use efficiency (EUE), was conducted using the Non-dominated Sorting Genetic Algorithm II (NSGA-II). By appropriately reducing the planting areas of maize and beets while increasing the planting areas of rice and oil crops to optimize the agricultural planting structure in 2022, economic benefits increased from 1.00 × 10¹⁰ CNY to 1.17 × 10¹⁰ CNY, WUE rose from 1.99 to 2.24, EUE improved from 0.28 to 0.30, crop output value grew from 1.04 × 10¹⁰ CNY to 1.21 × 10¹⁰ CNY, and total crop yields increased from 4.78 × 10⁹ kg to 5.26 × 10⁹ kg. These findings offer a practical solution to address irrigation challenges in sloping arid farmlands, contributing to enhanced food security and the sustainable use of agricultural resources in Xinjiang's dryland regions.