According to the 11th THW standard, we designed a pair of primers by which a segment of 256bp of HLA-DRB1, B3, B4, and B5 could be amplified simultaneously. Twenty-seven oligonucleotide probes were designed and synthesized for 39 loci on DRB1, 3 on DRB3, 1 on DRB4 and 3 on DRB5. A PCR-SSO DNA typing protocol was built, which met the standard of HLA class II DNA typing in 11th IHW. With this method, 186 of Chinese (Han) in Xi'an, 169 of Hui in Ningxia, 200 of Uygur in Xinjiang, and 188 of Tibetan in Tibet were detected with a comparison study. The genetic distribution of 46 loci of DRB in four ethnic healthy populations were surveyed. No diversity has been found between Han and Hui in DRB. DRB1 * 02(16.9%), DRB1 * 07 (13.1%), and DRB1 * 09(12.0%) were the higher frequent loci in Han. More DRB loci were detected in Tibetan but without higher loci as in Han and Hui. The DRB polymorphism of Uygur population was similar to Caucasian. A discriminative highest frequency of DRB1 * 07(23.8%) was found in Uygur, which implied a selection happened.