Development of Bracon hebetor Say parasitizing Indianmeal moth (Plodia interpunctella (Hubner) was studied at five temperature conditions (17, 20, 25, 28 and 32$pm$0.5$^{circ}C$) under a photoperiod of 16 : 8 (L : D). Developmental period (mean$pm$s.e.) of B. hebetor from egg to eclosion decreased from 28.6$pm$0.50 to 9.3 $pm$0.09 days and 28.1 $pm$0.51 to 9.2$pm$0.09 days for female and male, respectively, as the temperature increased from 17 to $32^{circ}C$. The combination model provided a good description of the relationship between temperature and development. The low temperature thresholds were estimated to be 14.0, 12.8, 15.1$^{circ}C$ for development of egg, larva and pupa. The thresholds for normal development (outside of the boundary layer of the development) were 14.0, 17.5, $15.1^{circ}C$ for egg, larva and pupa, respectively, indicating that the larval stage is more sensitive to the low temperature than the other stages. The results suggested that the present B. hebetor population could be another ecological race adapting to the seasonal temperature conditions of this area.