Abstract: In order to explore the genetic diversity and the maternal genetic evolution among different geographical populations of Liangshang black sheep, 60 black sheep from Puge County, Yanyuan County and Butuo County in Liangshan Yi Autonomous Prefecture of Sichuan Province were selected. There were 20 Black sheep in each county, half male and half female. The blood genomic DNA was extracted, and the mitochondrial DNA（mtDNA） D-loop sequence was amplified and sequenced by PCR. The mutation sites and haplotypes of the D-loop sequence of Black sheep were counted, and the haplotype diversity（Hd）, nucleotide diversity（Pi）,average nucleotide variation（K） and Tajima’s D value were calculated.The genetic distance between populations was analyzed and phylogenetic tree was constructed based on inheritance distance and haplotype. The results showed that the mtDNA D-loop sequence of black sheep had five lengths of 1 106, 1 176, 1 180, 1 811 and 1 182 bp, which were mainly divided into 1 180 bp and 1 811 bp.There were 101 mutation sites excluding insertion or deletion. There were 46 haplotypes, of which 8 were shared haplotypes. The haplotypes of different populations were quite different. The average value of Hd was 0.988; the average value of Pi was 0.016; the average value of K was 18.090, and the average value of Tajima’s D was-0.180 69.The genetic distance between Butuo black sheep and Puge black sheep and Yanyuan black sheep was far, but the genetic distance between Puge black sheep and Yanyuan black sheep was close.The black sheep of three geographical populations were distributed in branches A and B, of which clade A accounted for 76.7%.The results indicated that the black sheep of the three geographical populations had abundant genetic polymorphisms, and the genetic distance between them was relatively close, suggesting that they had at least two maternalorigins. In addition, the three populations of mtDNA D-loop sequences of black sheep from the three geographical populations belonged to neutral mutations, indicating that Liangshan black sheep only experienced natural selection, and there could be huge room for artificial selection in the future, so it was a type of sheep population that needs to be protected and was worth developing.