Abstract: To investigate the feasibility of microsatellite DNA in yak paternity identification applications, 17 microsatellite loci recommended by FAO were selected. The level of polymorphism of these microsatellite loci in Tianzhu White Yak groups was detected,and these 17 microsatellite loci for paternity exclusion probability cumulative was also calculated. Results were as followed： the average allele number of these microsatellite loci was 6.235 ;the polymorphism information content ranged from 0.191 to 0.824, with the average 0.608, showing high polymorphism;a candidate parent cumulative probability of exclusion was 0.997,and the two candidate parent cumulative probability of exclusion was 0.999 999 97;the null allele frequency of each microsatellite loci was below 0.05.Microsatellite DNA could be used for paternity identification in yak.