Two bio-insecticides, Biomctin and Tracer were evaluated for their toxicity as baits against peach fruit fly, Bactrocera zonata (Saunders) (Diptera: Tephritidae), in the laboratory, also their effects on some biochemical constituts of the fly were investigated. The results showed that, both Biomectin and Tracer showed toxic effects to B. zonata flies with LC₅₀ values of 2.39, 0.45 and 87.62, 5.61 ppm and LC₉₀ to 849, 83.85 and 11359, 139.45 ppm at 24 hrs and 48 hrs, for Biomctin and Tracer respectively. Results of biochemical analysis showed that, the amount of protein level decreased in treated flies to 54.5 and 29.2 mg/g. b.wt of Biomectin and Tracer respectively compared to 61.1mg/g. b.wt in the control. The activity of acetylcholine esterase also decrease in treated individuals to 692 and 727 µg/g.b.wt respectively compared to untreated ones 738 mg/g.b.wt. Level of alpha-esterases increased to 730.7 and 573 µg/g.b.wt. compared to control flies to 563.3 µg.g.b.wt. while the amount of beta-esterase showed no significant difference 193 and 182 µg/g.b.wt respectively after treatment compared to 189 µg/g.b.wt in the untreated flies. The amount of glutamic oxaloacetic transaminase (GOT) decreased in treated flies 28.7 and 43.7 Ux 10³/g.b.wt less than the untreated 113.3 Ux 10³/g.b.wt, while the amount of glutamic pyruvic transaminase (GPT) increased after treatment with Biomectin and decreased after treatment with Tracer 2707 and 1582 Ux 10³/g.b.wt, respectively compared to control ones 1937 Ux 10³/g.b.wt. Level of phenoloxidas increased in treated individuals 19.1 and 17.6 O.D. units/min/g.b.wt, respectively, than control 12.9. Level of lactate dehydrogenase also more in treated flies 718 and574 Ux 10³/g.b.wt more than control 496.3 Ux 10³/g.b.wt. This study improves that the two bio-pesticides cause toxic effects and biochemical changes in B. zonata and this may help to use them in its control instead of chemical insecticides.