Abstract: In order to exploring correlation of different nitrogen application level and group growth and Nitrogen utilization ratio of japonica rice in the cold region, ‘Longjing 21’ and ‘Kendao 12’ of Heilongjiang Province were used to study the effects of different nitrogen application level on group quality and nitrogen utilization ratio of japonica rice in the cold region. The results showed that, nitrogen fertilizer could significantly increase rice yield, but under conditions of the excessive nitrogen fertilizer, not only growth period was delayed and effective tiller rate reduced and group quality was deterioration, but also the yield did not reach high levels. Dry matter weight and LAI of full heading stage and yield had a conic relationship. And the best value of dry matter weight: ‘Longjing21’ was 9262.5±20 kg/hm2, ‘Kendao12’ was 8715.8±20 kg/hm2. The best value of LAI: ‘Longjing21’ was 5.2, ‘Kendao12’ was 5.04. At the same time, per unit area plants absorbed nitrogen fertilizer increased with the increase of nitrogen fertilizer application, but nitrogen fertilizer utilization ratio decreased, and the highest utilization ratio was N1 (44.44%, 42.9%). Nitrogen fertilizer requirement of 100 kg production was slightly different, but the difference between each treatment was not significant. N2 (pur N 135 kg/hm2) was more reasonable.