Using starch gel electrophoresis, we examined proteins specified by 41 presumptive loci representing two breeding populations of Rana subaquavocalis, a recently described species of leopard frog from Arizona. Individual and population levels of heterozygosity were low. Mean number of alleles detected (1.2) and mean levels of individual heterozygosity were higher at the Barchas Ranch location (0.042) compared with those from Ramsey Canyon (0.029). Nine loci among the 41 surveyed were polymorphic. Four of these were common to both populations. Each population was polymorphic for the remaining three loci, and each possessed one unique allele. Both populations went extinct by 1996.