To study nitrogen application and utilization rates in soybean leaves, we used the major soybean cultivar in the Sanjiang Plain of Heilongjiang province HeNong64 to analyze nitrogen accumulation and recovery rate in soybean leaves of the R₅ stage with the ¹⁵N tracing technique. Dry weight and nitrogen accumulation of soybean organs were significantly higher with 4.5 kg∙hm^-2 than other treatments. The dry weight of seeds was 22.7 g and the total plant dry weight was 73.2 g, which were significantly higher than without nitrogen application, by 17.92% and 16.38%, respectively. The nitrogen accumulation in seeds was 134.4 mg per plant and higher than without nitrogen application by 13.13%, so 4.5 kg∙hm^-2 was the most suitable leaf nitrogen application amount for HeNong64 in the R₅ stage. Under the tested nitrogen levels, ¹⁵N accumulation in different organs first increased then decreased with increasing nitrogen levels, and the ¹⁵N accumulation in seeds was the highest (9.96 mg per plant) with 4.5 kg∙hm^-2 treatment. Therefore, 4.5 kg∙hm^-2 was the most suitable leaf nitrogen application amount for HeNong64 and leaf nitrogen was the main source of nitrogen for seeds. Under the same nitrogen application level, ¹⁵N accumulation in different organs was in the order of seed>stem>leaf>pod> petiole>root and the nitrogen accumulation was significantly higher in seeds than in other organs in the R₅ stage. The ¹⁵N contribution rate and plant nitrogen recovery rate in seeds with 3.5 kg∙hm^-2 was highest, so nitrogen was easier to be absorbed with lower leaf nitrogen application, but its net accumulation was lower than 4.5 kg∙hm^-2 and the plant nitrogen recovery rate was higher than 4.5 kg∙hm^-2.