9012AB is a recesive genic male sterility (RGMS) line in rapesed, of which the male sterility is controlled by two pairs of recesive duplicate male sterile genes (Bnms3 and Bnms4) esp). The recesive homozygosity at the esp l o c u s (espesp) can supres the expresion of the recesive male sterility trait in homozygous plants (Bnms3Bnms3Bnms4Bnms4) and result in fertility restoration. A F2 population of 18 plants, derived from self-pollinated progenies of a 9012 AB fertile plants ( ), was conducted to identify molecular markers linked to the recesive male sterility gene (Bnms3). By amplified fragment length polymorphism (AFLP) assay combining with bulked segregant analysis (BSA), 13 markers linked to Bnms3 were identified. Linkage analysis indicated that 13 AFLP markers were tightly linked to the Bnms3 ng them, one marker was co-dominant marker, 6 markers were in coupling phase with Bnms3, and the others were in repulsion phase with Bnms3 gene, One AFLP marker with a genetic distance of 1.4cM was further converted into a SCAR marker successfuly, which have ben aplied in marker-asisted selection of RGMS lines and their temporary mai