In order to investigate the effects of different irrigation and fertilization conditions on the growth of maize at different fertility stages in the Loop irrigation area, three irrigation levels of low water (1 800 m³/hm²), medium water (2 250 m³/hm²) and high water (2 700 m³/hm²), and three fertilization levels of low (300 kg/hm²), medium (375 kg/hm²) and high (450 kg/hm²) fertilization were investigated using maize "Jinping628" as the material, respectively. At the same time, the local irrigation and fertilization amount were used as the control group (CK). The effects of 10 treatments on soil moisture, nutrient and maize growth in the seedling stage, jointing stage, tasseling stage, filling stage and maturity stage were analyzed. Based on the results, it was found that the average soil water content tended to decrease after the pulling stage. Maize water consumption was highest during the pulling and filling stages, accounting for more than 65% of water consumption during the entire reproductive period. Soil nitrate-nitrogen accumulation was minimal during the pull-out stage, and plants absorbed large amounts of nutrients for rapid maize growth. Under high water levels, maize yield and water-use efficiency tended to increase and then decrease with irrigation and fertilization. Through multiple stepwise regression analysis, the effects of soil moisture and nutrients on maize growth in different growth stages were screened out. The results showed that soil moisture had a greater influence on maize growth than soil nutrients at tasseling, filling and maturity stages, and soil nutrients at jointing stage had a greater impact on maize growth than soil moisture. The results of the study can provide a theoretical basis for water conservation and reduction of chemical fertilizer use in the loop irrigation area, rational allocation of water resources, reduction of nitrogen surface pollution, and ensuring stable growth of maize.