The grain yield and quality of spring maize were investigated with the varieties of"Xianyu 335"under the different densities（45 000,67 500,90 000 plant/ha） and different nitrogen rates（N 0.0,N 112.5,N 225.0,N 337.5 kg/ha）. The results showed that compared with the 67 500 plant/ha, the grain yield under 90 000 plant/ha treatment were significantly improved. The increase of nitrogen rate could effectively increase the grain yield and dry matter accumulation. The grain yield under N 337.5 kg/ha is significantly higher than the other two treatments, but it is not visibly different with N 225.0 kg/ha. The effect of planting density and nitrogen rate on fat and starch content was not significant. By adding nitrogen rate can significantly increase protein content. The protein content under N 337.5 kg/ha was higher than the other treatments. The variance analysis showed that planting density, nitrogen rate and the interaction had significant effects on the grain yield and protein content.