Abstract: The seven native sheep breeds of western China were analyzed using 30 microsatellite markers which we selected. The allele frequency, mean heterozygosity, polymorphism information content, effective allele number and dendrogram analysis with coancestry genetic distance were used to assess the genetic variability between and among breeds. The results showed that total of 239 alleles were detected, the mean allele number of one locus was 8, the effect allele numbers were between 2.9 and 3.4 in breeds, and the mean Ne of loci were from 1.9 to 5.3. The mean heterozygosity of loci from 0.320 to 0.818, mean heterozygosity of breeds were from 0.656 to 0.719, and mean polymorphism information content of loci were from 0.388 to 0.786, mean PIC of breeds from 0.590 to 0.666. The dendrogram relationship between different sheep breeds were generally in accordance with the origins, breeding history and localities. The different opinions about the results need deeper research work.