The experiment was carried out in the canopy.Xiang You 15 was regarded as our experiment material，and the 15N tracer technique was taken.Two nitrogen levels were set up under the condition of potted plant，the accumulation of dry matter，nitrogen accumulation and distribution and 15N abundance during the rapeseed early flowering，full bloom，final flowering，bean stage and mature period were compared and researched to reveal the absorption characteristics of nitrogen fertilizer and the redistribution of nitrogen in the root system of rapeseed，and to provide a theoretical basis for efficient nitrogen management and high-yield cultivation of rapeseed.The results showed that: in the late stage of rape，the amount of nitrogen accumulation in the root was not significant，and the change of nitrogen accumulation in the stem showed the single peak mode，which reached the maximum during the flowering period.The amount of nitrogen accumulation of leaves decreased significantly not in the early flowering period but inthe final flowering stage.The amount of nitrogen accumulation in the silique showed the S pattern，which increased slowly before the final flowering period，after that increased rapidly until the fruiting period，and then increased a little.The amount of nitrogen accumulation in the stem from the flowering period began slowly.The pod skin accumulated to the highest in the final flowering period，then gradually decreased.The pod carpel decreased slightly after the final flowering period，but the change was small.At the low level of nitrogen，61.98% of the rape nitrogen came from soil，and 38.02% came from fertilizer，which indicated that the proportion of nitrogen from the soil was higher than that from fertilizer.In the high nitrogen level，the percentage of total accumulated nitrogen of rapeseed from fertilizer was 52.69%，compared with the 47.31% from the soil，and the percentage of the accumulation of nitrogen in silique and stem was significantly higher than from the soil.The proportion was close for root，pod skin and pod carpel in the accumulation of nitrogen in soil or fertilizer.In the later stage of rapeseed，there was still a large demand for nitrogen，but also had a strong ability to absorb and accumulate nitrogen.