Premise of the study: Pritchardia (loulu palm) is the seventh largest flowering plant genus in the Hawaiian archipelago, and many species are of high conservation concern. The island radiation has produced many cryptic species complexes across fine ecological gradients. Microsatellite primers were optimized to investigate genetic diversity of Pritchardia martii (Gaudich.) H. Wendl. and species boundaries among the Hawaiian Pritchardia. Methods and Results: Six new loci and three previously described loci for a closely related genus, Phoenix, were optimized and tested. Five loci were polymorphic, and 72 alleles were detected across loci within P. martii. The five loci were also polymorphic across the other 27 currently recognized Pritchardia species. Conclusions: These results indicate the utility of these microsatellite markers for understanding the conservation genetics of P. martii and species delimitation and hybridization across the genus. © 2011 Botanical Society of America.