As a first step toward cloning the genic multiple allele inherited male-sterile gene Ms in Chinese cabbage (Brassica rapa L. ssp pekinensis (Lour.) Olsson), we attempted the molecular tagging of this male-sterility locus using the amplified fragment length polymorphism (AFLP) technique. A BC 1 mapping population (130 plants) segregating for male sterility/fertility was constructed for the tagging using the bulked segregant analysis (BSA) method. Screening 144 primer combinations, four AFLP markers were identified to be tightly linked to the Ms gene, the nearest one of which, AFLP01, was converted to a SCAR marker for the markerassisted selection (MAS). Finally, a genetic map of the Ms gene was constructed with four AFLP markers and one SCAR marker, covering a total interval of 13.9 cM. Two markers AFLP01(SCAR01) and AFLP04 flanked the Ms locus at distances of 2.3 and 7.8 cM, respectively.