Crop water requirement varies with the growth stage, so water-saving effect of alternate partial root zone irrigation (AI) also varies with the growth stage. Understanding the effect of alternate partial root-zone irrigation at different growth stages on maize growth and water and nutrient utilization can provide the theoretical foundation for the implement of alternate partial root zone irrigation and fully exerting its effect of saving water and fertilizer. Taking conventional irrigation (CI) as the control, this study has investigated the effects of AI respectively at seedling- early grain filling, seedling-jointing and jointing-tasselling stages on dry mass, nitrogen and potassium contents and uptakes of maize and available N and K contents in soil using a pot experiment under two irrigation levels (normal irrigation and mild water deficit) and two ratios of inorganic to organic N (100% inorganic N and 70% inorganic N + 30% organic N). Results indicate that under mild water deficit and combined application of organic and inorganic N fertilizer condition, AI at the jointing-tasselling stage increased shoot and total dry masses by 29.6% and 27.4%, and shoot and total N uptakes by 50.7% and 50.4%, respectively, if compared to CI. Combined application of organic and inorganic N increased shoot and total N uptakes to some extent, but generally reduced soil available N and K contents when compared to only inorganic N. Thus alternate partial root-zone irrigation at the jointing-tasselling stage could increase total dry mass and N uptakes under mild water deficit and combined application of organic and inorganic N fertilizer.