Abstract: This study utilized two distinct rapeseed varieties, Xiangyou 15 with high nitrogen fertilizer absorption efficiency and R210 with low nitrogen fertilizer absorption efficiency, to produce an F1 hybrid. A doubled haploid（DH） population comprising 180 lines was obtained through microspore culture. Phenotypic investigation and QTL analysis were conducted on traits closely related to nitrogen fertilizer absorption efficiency in rapeseed under two nitrogen fertilization levels, including basal stem diameter, effective pod number per plant, aboveground dry weight per plant, and nitrogen absorption efficiency. The results showed that a high-density genetic map was constructed, covering 19 chromosomes of rapeseed, comprising 42751 polymorphic SNP markers, 4302 bins, with a genome coverage of 2959.89 cM and an average interval of 0.69 cM between adjacent bins. Based on this map, using the composite interval mapping method（CIM）, 14 QTLs were detected under two nitrogen application levels, with individual QTL explaining 5.24% to 18.22% of the phenotypic variation. Seven candidate genes and one p-loop containing nucleoside triphosphate hydrolases superfamily protein of chloroplastic-like potentially associated with nitrogen use efficiency traits in rapeseed were identified. These QTLs and candidate genes will provide valuable information for the genetic improvement of nitrogen use efficiency in rapeseed.