Trichogramma wasp is one of the most successful parasitic species in the world, mainly used to control many pests. The effects of field (RC) and half recommended concentrations (half RC) of four Insecticides: 1. Tetraniliprole, 2. Chlorantraniliprole 3. Lufenuron, and 4. Thiocyclam was studied in different preimaginal stages of 1. Trichogramma brassicae Bezdenko and 2. Trichogramma evanescens Westwood (Hymenoptera: Trichogrammatidae). Parasitized eggs of the angoumois grain moth Sitotroga cerealella Olivier (Lepidoptera: Gelechiidae) were treated by 1. The dipping method at the larval, 2. Prepupal, and 3. Pupal stages of the parasitoid. For persistence evaluation, the Insecticides were applied at the recommended concentration on tomato plants in a pot by a hand sprayer till the Runoff point. Plants were maintained under a transparent polyethylene rain cover in the field. Leaves of the treated tomato plants were sampled and transferred to the laboratory at time intervals of 3, 5, 16, and 31 days after application. In this experiment were adults (< 24 hours old) of T. brassicae and T. evanescens. Based on our results, thiocyclam at both RC and half RC was the most harmful insecticide for immature stages of both parasitoids. This insecticide at the prepupal stage (at both RC and half RC) had more adverse effects than in pupal or larval stages. Tetraniliprole, with 23.33% and 21.11% mortality in less than five days, was classified as the short-lived insecticide for T. brassicae and T. evanescens, respectively. The same result was obtained in the chlorantraniliprole treatment. That caused 25% and 26.11% mortality to the parasitoids, T. brassicae, and T. evanescens. Lufenuron, with 30.55% and 30.00% mortality in less than five days, was short-lived. However, thiocyclam, with 14.44% and 16.67% mortality in less than 30 days and 65.55% and 69.44% mortality in less than five days, was classified as moderately persistent for those two species. Therefore, according to the results, 1. tetraniliprole, 2. chlorantraniliprole, and 3. lufenuron can control lepidopteran pests by observing the appropriate spraying distance to release Trichogramma wasps. Thiocyclam, on the other hand, should be employed with extreme caution.