The genetic diversity and population structure of eighteen Potentilla fragariodes var. major (Rosaceae) populations in Korea were determined using genetic variations at 22 allozyme loci. The percent of polymorphic loci within the enzymes was 66.7%. Genetic diversity at the species level and at the population level was high (Hes=0.203; Hep=0.185, respectively), whereas the extent of the populaton divergence was relatively low (GST=0.069). FIS, a measure of the deviation from random mating within the 18 populations, was 0.075. An indirect estimate of the number of migrants per generation (Nm=3.36) indicated that gene flow was high among Korean populations of the species. In addition, analysis of fixation indices revealed a slight heterozygote deficiency in some populations and at some loci. Wide geographic ranges, perennial herbaceous nature and the persistence of multiple generations are associated with the high level of genetic variation. Although P. fragariodes var. major usually propagated by asexually-produced ramets, we could not rule out the possibility that sexual reproduction occurred at a low rate becasue each ramet may produce terminal flowers. Mean genetic identity between populations was 0.983. It is highly probable that directional movement toward genetic uniformity in a relatively homogeneous habiat operates among Korean populations of P. fragariodes var. major.