The nitrogen requirements of plants are different at different times.In order to understand the nitrogen distribution characteristics and nutrition requirements of wine grapes at the eastern foot of Helan Mountain in Ningxia，the 7-year-old“ Cabernet Sauvignon” was taken as the research object，and nitrogen was applied at 255.10 g per plant(10 g15N-ammonium sulfate+245.10 g ordinary ammonium sulfate).Using 15N isotope tracing technology，soil and wine grape roots and stems(stems were divided into main stem，first branch，and second branch)were collected at 35，70，105，140 and 160 d after nitrogen application，the 15N abundance and total nitrogen content of leaves and fruits were determined and analyzed.The contribution rate(Ndff)，distribution rate，nitrogen utilization rate，residual rate，and loss rate of the 15N absorbed and distributed in each organ from fertilizer at different times were calculated.The results showed that the dry matter content increased significantly from 70 to 105 d after nitrogen application，the dry matter content of roots，main stems，primary branches，secondary branches，leaves and fruits at 105 d after nitrogen application were 95.19%，4.23%，6.51%，58.58%，30.00% and 219.84% higher than those at 70 d after nitrogen application，respectively.The Ndff value increased obviously from 70 to 105 d after nitrogen application，the Ndff values of roots，main stems，primary branches，secondary branches，leaves and fruits at 105 d after nitrogen application increased by 6.38，5.89，5.87，7.25，4.34 and 7.01 percentage points compared with those at 70 d after nitrogen application，respectively.The 15N distribution rate of roots at 35 d after nitrogen application was the highest，which was 1.46%.The 15N distribution rate of ain stems，primary branches，secondary branches at 160 d after nitrogen application was higher than other periods.The 15N distribution rates of roots，main stems，primary branches，secondary branches，leaves and fruits all increased significantly from 70 to 105 d after nitrogen application.The 15N distribution rates at 105 d after nitrogen application were higher than those at 70 d after nitrogen application with an increase of 5.26，0.52，0.24，2.55，3.70 and 3.21 percentage points.In summary，the peak period of nitrogen absorption for wine grapes was from 70 to 105 d after nitrogen application.During this period，attention should be paid to the application of nitrogen fertilizer.During the entire nitrogen application period，the nitrogen utilization rate of wine grapes was 38.97%，the residual nitrogen fertilizer rate was 17.77%，and the nitrogen loss rate was 43.25%.