The side-effect of six insecticides get to be used on apple trees in Syria were tested on the adults of the egg parasitoid Trichogramma cacoeciae Marchal. Using the exposure of adults to treatment glass plates for 24 hours. The highest recommended field application rate was applied. The classification of the International Organization for Biological Control for insecticides effect in adults mortality or reducing of parasitism was used (1, Harmless; 2, slightly harmful; 3, moderately harmful; 4, harmless). This study showed that Cloropyrifos, Deltamethrin and Acetamiprid and caused adults mortality 100%, and classified as harmful insecticides (glass 4) according to IOBC. While Diflubenzuron, lufenuron and fenoxycarb were slightly harmful in adults mortality (class 2) according to IOBC. Whereas was harmful to larval stage only, and moderately harmful to the egg and pupae. Acetamiprid was also harmful to the egg stage and moderately harmful to larvae and pupae. Whereas the insect growth regulator insecticides and the insect growth inhibitors (Diflubenzuron, Lufenuron and Fenoxycarb) caused reducing in parasitism (82.05, 56.03, 94.40)% for the three insecticides respectively, and classified (class 2, 2, 3) respectively according IOBC category compared with the parasitism in control 89.25%, also the latest three insecticides reduced significantly the longevity of adults which were survived after the exposure to treatment class plate compared with the control.