Indianmeal moth Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae) is an important pest of stored grains products. As a natural enemy, an ectoparasitoid Bracon hebetor Say (Hymenoptera, Braconidae) has been used to control Lepidopteran pest insects. Venom from parasitoid female alters many physiological functions in host insects. However, mechanism of physiological response of host insects against envenomation and parasitization is not clear. Here we observed the effect of B. hebetor envenomation on the gene expression (shsp, hsp70, grp78 and hsp90) in P. interpunctella at different time intervals of post envenomation. Fifth instar day 5 larvae of P. interpunctella were used in experiment to observe the effect of envenomation. Our results showed that parasitoid envenomation affected the gene expression differently in host insect. This study will provide comprehensive insights on physiological and biochemical mechanism in host-parasitoid relationships.