Population genetic structure ofPrimula sikkimensis distributed in Himalayan．Hengduan Mountains was studied using Inter-simple sequence repeat(ISSR)markers．Ten ISSR primers were used to amplify 254 individuals of 13 populations，which successfully detected 91 loci，all of which being polymorphic．The Shannon diversity index(HO)ranged from O.2293 to O.4016，with an average of 0.321l at the population level(HPOP)and O.5576 at the species level(HSP )．Moreover，the AMOVA analysis showed that 50.28％ of the total genetic diversity was among populations；the index(GST=0.4127) based on POPGENE indicated tIlat 41.27％of molecular variation was among populations． which was lower than that in the result of AMOVA． The variation of genetic distance ranged from 0.0780 to 0.4748，genetic identity from 0.6220 to 0.9250．In addition, the gene flow am ong population was low (Nm=0.7l14)；relatively lower gene flow might be one of important factors influencing the genetic structure of the species．The present analysis reveals that 13 populations of P sikkimensis in Himalayan-Hengduan Mountains have high genetic diversity and high genetic diferentiation.