none Laboratory trials were undertaken to investigate certain biologicl aspects of the braconid ectoparasitoid, Bracon brevicornis Wesmael on larvae of the corn borer, Sesamia cretica Led. at seven different constant temperatures ranging from 10-40 degree C. It was found that the parasitoid did not deposit any eggs at the two extreme tempertures, 10 and 40 degree C, whereas successful oviposition and development occurred between 15 and 35 degree C, inclusive. Number of deposited eggs, number of formed cocoons, and number of emerged adults/host larva increased positively with temperature between 15 and 35 degree C. On the other hand, periods of cocoon stage and total developmental period of the parasitoid decreased with the increase in temperature. The total developmental period ranged from 47 days at 15 degree C to 8 days at 35 degree C. The color of produced adults was considerably affected by the rearing temperature. These colors ranged from black at 15 degree C to pale brownish-yellow at 35 degree C. Longevity of the parasitoid parents which were kept with S. cretica larva decreased with the increase in temperature. In all cases, adult females had significantly longer life span than males at any given temperture. The longest life span (88 days) was recorded for females at 10 degree C. It is concluded that most appropriate temperatures for laboratory mass rearing of the parasitoid seem to be 30-35 degree C, and that cold storage of the adults at 10 degree C helps for a longer life span for successful shipping or timing of appropriate field liberation.