Abstract: The yield and quality of maize are affected in many ways. Three maize varieties, Chuandan 99, Zhengda 719 and Zhengda811, were selected as the research objects. The effects of different planting densities（6.50×104plants/hm~2, 7.25×104plants/hm~2and8.00×104plants/hm~2） on the number of grains per ear, ear number, thousand grain quality and yield of maize were tested. It was found that when the planting density of maize increased from 6.50×104plants/hm~2to 8.00×104plants/hm~2, the number of grains per ear, thousand grain weight and ear number of maize of the same variety showed a decreasing trend. With the increase of planting density of maize plants, the yield of different maize varieties showed an increasing trend. It was found that with the increase of maize planting density, the empty culm rate and yield per plant increased and the yield per plant decreased.