Using the brown soil as the tested soil, pot experiment was conducted to investigate the effects of biochar derived from rice husk on soil nitrogen content, rape yield, nitrogen contents of aboveground and underground of rape, and the loss of N₂O gas under two consecutive cropping seasons using ¹⁵N tracing method. Nitrogen utilization efficiency of nitrogen fertilizer and the proportion of different fate were calculated to study the effect of biochar addition on uptake and transport of nitrogen in rape. Biochar was applied at four rates (0, 0.5%, 1% and 2%) to the soil. The results showed that biochar application significantly increased the yield of rape in the first and the second cropping seasons. Compared with no biochar addition, the ratio of soil nitrogen uptake by rape was increased by 2% in the first season in the treatment of 0.5% biochar application, and it was increased by 0.8%, 2.4% and 3.2% in the second cropping season, in the treatments of 0.5%, 1% and 2% biochar application, respectively. The nitrogen contents of leaves and roots increased with the increasing of biochar application. Compared with no biochar addition, biochar application significantly decreased N₂O gas emission of rape in the two seasons, and the N₂O gas emission reduced amount was 0.30 and 0.10 mg/kg in the first season and the second season, respectively, in the treatment of 2% biochar application. Compared with no biochar addition, nitrogen utilization efficiency of rape increased by 16.3% in the treatment of 2% biochar application. The average nitrogen utilization efficiency of two seasons increased by 0.42%, 0.72% and 5.3% in the treatment of 0.5%, 1% and 2% biochar application, respectively. Thus, 2% biochar application should be considered as a suitable soil amendment.