Abstract:Combining a DH(Double Haploid)lines(348 lines)in Brassica napus and constructed genetic linkage group,we detected and analyzed QTL for thousandseed weight (TSW) by composite interval mapping model in 2009-2013 in Dali of Shaanxi Province. A total of 46 significant identified QTLs for TSW were obtained and mainly located on A7, C1 and C6 chromosomes, etc. The maximum of phenotypic variation was qTSW09DL111 which reached to 19.63%, and the minimum of phenotypic variation was qTSW11DL9 which only explained 2.73%. The identified QTLs were integrated into consensus QTLs by metaanalysis and cqTSWC12 reached to 10.64% of phenotypic variation. Some consensus QTLs were repeatedly detected, cqTSWC13, for example, was repeatedly detected in five consecutive years, indicating QTLs for TSW were expressed stably in different environments. Meanwhile, the major QTL cqTSWC12 was regarded as a new QTL on C1 chromosome. The genomic information of these QTLs will be conducive for the construction of near isogenic line, fining mapping and Mapbased cloning. The results provide an important theoretical guidance for molecular breeding and developing high seed yield varieties in Brassica napus.