Maize and Sorghum are the major staple food crops in the tropics. Of many insects that attackrnthese crops Chilo partellus (Swinehoe) (Lepidoptera: Crambidae) is the most notoriousrnspecies. Cotesia flavipes Cameron (Hymenoptera: Braconidae) is a co-evolved parasitoid ofrnC. partellus and has been utilized as a biological control of stemborers including C. partellusrnin many countries.rnBy measuring some life history parameters, the variability of C. flavipes from tworndifferent geographic locations, which were reared on two different geographicrnpopulations of C. partellus, was studied. The parameters taken were suitability test,rndevelopmental time, realized fecundity and longevity. The suitability test was studiedrnat constant temperature of 28oc, while developmental time, realized fecundity andrnlongevity were studied at constant temperatures of 20oc, 25oc, 28oc and 30oc. All thernexperiments were studied under 12L: 12D photoperiod and a relative humidity of 50-rn60%. Data were analyzed using SPSS computer software, when ANOVA results werernsignificant, means were separated by Tukeyâ€™s studentized test (HSD).rnIn the suitability test, the best population interaction was when C. partellus and C. flavipesrnpopulations were from the same geographic area. Both populations of C. flavipes have shownrnvariability when the hosts were from different geographic populations. The developmentalrntime of C. flavipes increased as the temperature increased, however, the total progenyrnproduced per female and longevity increased as the temperature decreased. Effect ofrntemperature and populations were seen in most of the life history of C. flavipes, which arernbases for successful establishment and efficient parasitism.