Abstract: In order to elucidate the response of plant type and yield traits of different maize varieties to planting density, six maize varieties (‘Zhengdan958’, ‘Xianyu335’, ‘Weike702’, ‘Xundan20’, ‘Jinhai5hao’ and ‘Limin33’) that are now planted widely in production were used as materials, the plant type and yield trait changes of different maize varieties under four planting densities (60000 plants/hm2, 90000 plants /hm2, 112500 plants /hm2, 127500 plants /hm2) were analyzed. The results indicated that the three ear leaves area and the coefficient in stem diameter of six varieties both were decreased with the increase of planting density. But the reduced range was difference among different varieties or different ear leaves. Yield component factors, such as ear length, ear diameter, rows per ear, kernels per row, kernels per ear and 1000-grain weight, were showed decreasing with the planting density increasing. Among four planting densities, the yield of ‘Jinhai5hao’, ‘Weike702’ or ‘Zhengdan958’ under the density of 90000 plants/hm2 was the highest; other three variety yields were showed reducing with the increasing of planting density. Based on the regression analysis, the effect of the kernels per ear on yield was the largest one among the ten factors that are known affecting maize yield, secondly for the kernels per row. The results will be providing the theoretical basis for the maize variety breeding and the high efficient planting in maize production.