Trichogramma pretiosum is a key natural enemy of heliothis (Helicoverpa spp. ) on the Darling Downs. The data presented here describe some of the biological parameters of T. pretiosum, and may be useful in future population models that predict the impact of this valuable egg parasitoid on heliothis. Here we report on the lifespan, parasitism levels and progeny production of T. pretiosum reared on Helilicoverpa armigera in the laboratory.