Allele frequencies and haplotypes of 11 Y-chromosome STR loci, DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385 ab, DYS438, DYS439 and DYS437 were determined in 320 unrelated Yunnan Han Chinese males. A total of 293 haplotypes were identified, of which 268 were unique, 23 were shared in two individuals, and 2 were shared in three individuals. The allele diversity values for each locus ranged from 0.4087 (DYS438) to 0.9701 (DYS385). The allele observed haplotypes diversity value was 0.9994. The combined Y-chromosome STR polymorphisms provide a powerful discrimination tool for routine forensic applications.