The experiments were carried out in the laboratory, green houses and the fields for studying some biological characters of some beneficial insects on certain important vegetable crops .These experiments were conducted during the three successive seasons in Egypt . The aim of these trials was to evaluate the possibility of using the reared aphid parasitoid and the coccinellid predatory insects coccinella septempunctata , C.undecimpunctata L., Cydonia vicina isis Gr, Hippodamia tridecimpunctata L. and Exochomus nigromaculatus (Goeze) , for the biological control of certain aphid species.