This paper describes the physiological effects of Granulosis virus (SpliGV), Spinosad and Azadirachtin on male and female internal reproductive system when treated with sub lethal concentrations (3.48x10⁷ OB/ml, 0.14 mg/ml and 1.38 mg/ml), are applied by ingestion of newly moulted third instar of the cotton leaf worm Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae). The male reproduction system parts have affected in length and width by treatments. Larvae treated with SpliGV and Azadirachtin had short lengths of some parts of male reproductive system. In the testes longitudinal section of larvae treated with SpliGV had defective in the testes follicles development and shortage of spermatocytes, treated with Azadirachtin showed some follicles with minor wall thickness and disorganization of spermatocytes. Spinosad have delayed the development of spermatozoids. In male pupae five days were observed the first alteration in the spermatogenesis development, mainly found in larvae treated with Azadirachtin. But in pupae nine days coming from larvae treated with SpliGV were observed smaller amount of primary and secondary spermatocytes, in adult three days too observed little amount of spermatids and sperm bundles. In the treatment with Spinosad, pupae nine days observed small amount of spermatocytes, spermatids and sperm bundles, in adult with three days found that delayed in spermatozoids development. In female did not found effects in all treatment on the oocytes production in both virgin and mated. Female virgin three days had greater number of oocytes than mated. The female coming from treatments with Azadirchtin and Spinosad presented longer ovarioles and with greater number of oocytes.