Abstract: Maize is the main crop in the Loess Plateau. Farmers invest heavily in tertilizers to obtain higher yields, which resuhs in deterioration of soil physical and chemical properties and reduced crop yields. Application of organic manure is one of the effective measures. Five treatments were designed for this experiment. The organic fertilizer dosages were 0 kg/hm^2 （M0）, 11 250 kg/hm^2 （M1）, 22 500 kg/hm^2 （M2）, 33 750 kg/hm^2 （M3） and 45 000 kg/hm^2 （M4）. Analysis of differences in leaf area index, material production, water use, and yield formation of difterent treatments showed that： the application of chemical fertilizers combined with organic fertilizer can significantly increase the leaf area index, dry matter accumulation, water use efficiency, and yield of maize plants. When the fertilizer application rate was 22 500 kg/hm^2, various indicators performed well. The leaf area index was 4.58, which was 8.30% higher than that of the control; the dry matter accumulation was 513 g/plant, which was 8.20% higher than the control; the water use efficiency was 25.98 kg/（mm·hm^2）, 31.40% higher than the control, and the grain yield was 10 136.20 kg/hm^2, 30.25% higher than the control. Therefbre, increasing 22 500 kg/hm^2 of organic fertilizer can be an efteetive technical measure to increase the local maize yield potential.