The effects of NCNPs on nitrogen transformation and use efficiency were studied to provide theory basis for NCNPs application and to explore approaches of increasing rapeseed yield and improving nitrogen use efficiency.A pot culture experiment was carried out with rapeseed cultivar Xiangyou 15 in the biological park of Hunan university of science and technology.Six treatments(CK,CK1,CK2,T1，T2，T3)were set up and each treatment had 3 pots and each pot had 4 plants.T1，T2 and T3 treatment were used for NCNPs adding urea,CK2 treatment was used for DCD adding urea,CK1 treatment was used for urea.The results showed that,the process of nitration was obviously restrained with NCNPs,compared with the CK1 treatment,the NH+4-N content increased by 118% and the NO-3N content decrease of 49.74 mg/kg.The NCNPS application significantly improved N accumulation in leaf,stem and root at seeding stage,and increased dry matter accumulation of rapeseed plant.The rapeseed was strongly inhibited with increases NCNPs concentrations to 15‰.In conclusion,the optimal application rate of NCNPs was 5‰ with N application,which increased the fertilizer N use efficiency,and promoted the rapeseed growth and N utilization at early growth stages significantly.