none The effect of lethal high temperature with vacuum on the parasitoid, Bracon hebetor Say was studied in the laboratory during 1984 and 1985. Results showed that the combined effect of temperature and vacuum was more lethal to all stages of the wasp than was the temperature or vacuum alone. In the temperature with vacuum treatment, the eggs were more susceptible than the other immature stages at 35 and 40 degree C, while at 40 degree C with vacuum, larvae showed higher sensitivity than the egg of the pupae. The pupal stage appeared to be more resistant particularly at 35 and 40 degree C under vacuum. The LT50s were 59 and 30 min. at 35 degree and 40 degree C respectively. Complete mortality of the parasite was obtained in 300 and 60 min. when exposing the pupae to 35 and 40 degree C with vacuum, respectively. Adults were very sensitive to all temperatures. All stages were severely affected by exposing the parasite to 50 degree C plus vacuum. Results also indicated that the biotic potential of the surviving wasp was reduced after exposing to temperature with vaccum. The possibility of utilizing the parasite, Bracon hebetor in an integrating mean with temperature plus vacuum against the fig moth, Ephestia cautella in date warehouse is discussed.