In biological control, identification of species is the first step. It is especially difficult for the genus Trichogramma (Hymenoptera: Trichogrammatidae) because of their minute size and lack of reliable morphological characters. In the study, random amplified polymorphic DNA polymerase chain reaction (RAPD-PCR) banding patterns were used for characterization of three laboratory cultures that represented two Trichogramma species [Trichogramma brassicae (Bezdenko) ve Trichogramma euproctidis (Girault)]. Thirteen of the fifteen primers were used individually to discriminate the species. Genetic variation and distance within and between species with respect to proportion of shared bands were clarified. Genetic distances within species were much lower (0.8%) than between species (68%). Our results suggest that the RAPD technique could be used to improve identification and to better understand the genetic polymorphism of Trichogramma spp. Potential uses of RAPD-PCR in genetic analyses on parasitic Hymenoptera are discussed in the study.