In this study, esterase variation was investigated for one Trichogramma turkestanica Meyer and two Trichogramma brassicae Bezdenko populations collected from Southeast Turkey. Depending on the banding patterns there were slower (Est1) and faster (Est2) bands as two different isozymes were determined. T. turkestanica had a different banding pattern than T. brassicae. At the same time, numbers of parasitized eggs and female and male offspring, and adult longevity were determined for each population. There were no significant differences between cultures except adult longevity. Some morphometric characters of cultures were also measured, comprising body length, flagellum length, head width, the longest seta of the flagellum, hind tibia and hind wing length. All characters were similar between the two T. brassicae populations and were significantly different from T. turkestanica.