Abstract: Esterase isozyme electrophoresis was used as a method for identification of five Cymbopogon species and seven cultivars of C. flexuosus Nees ex Steud. Two regions (slow and fast moving) of banding pattern were observed in all the material tested. A maximum of nine esterase isozymes were observed in different Cymbopogon species. species. Isozymes in different species ranged from 2 (C. flexuosus and C. citratus) 5 (C. martinii). The study revealed that all the C. flexuosus cultivars tested could be categorized as geraniol or citral rich by resemblance of their esterase isozymes pattern either with geraniol rich mutant cv. GRL-1 or normal citral rich cv. OD-19. All the Cymbopogon species had unique banding patterns, the only common feature being that all of them, except C. pendulus was isozyme Rf = 0.41. Only three species C. pendulus, C. winterianus and C. martinii could be uniquely identified on the basis of their esterase isozyme patterns. C. flexuosus and C. citratus showed identical esterase isozymes patterns.