Laboratory trails were conducted to determine the effectiveness of zinc oxide nano-particles (ZnONPs) compared to the chitin synthesis, nomolt and bio- insecticide, emacte compounds against the first instar larvae of Earias insulana. Toxicity effect of the tested compounds on the first instar larvae with some biological aspects and chemical analysis were studied. The results revealed that LC_50s were 7.593, 29.32 and 0.536 ppm, when newly hatched larvae of E. insulana treated with (ZnONPs), nomolt and emacte, respectively. Obtained data also indicated an increase in larval duration to 20, 25, 23.3and 18.0 days, for the aforementioned compounds, respectively, compared to 13.96 days for control. All treatments prolonged pupal periods compared to control, and caused highly reduction in the weight of larva and pupa stages, (ZnONPs) treatment was the most efficient in this matter as it resulted 91.1% and 93.73% reduction in larval and pupal weight, respectively, compared to control. The reduction in larval and pupal weight led to increase in the malformation and mortality percentages which recorded 77, 79 &74 % for, ZnONPs, nomolt and emacte treatments, respectively. According to biochemical analysis, all treatments reduced the level of the important total soluble protein, lipid and carbohydrate contents which play an important in the physiological, metamorphosis and developmental process of E. insulana during immature stages. In addition, (ZnONPs) and emacte treatments caused a high decrease in phenoloxidase which necessary in melanin production in cuticle formation, N-acetyl- glucosamine and chitinase activity. On contrast the chitinase activity was increased (1.5 times) approximatily in case of nomolt, treatment as compared to control.