The biological and biochemical effects of the two plant extracts i.e. lemon and orange peels were studied on the Black Cut Worm (BON) Agrotis ipsllon. For the biological studies, of the second instar larvae were treated by series concentrations of each extract (0.25, 0.50, 1, 2 and 4%). To determine the aspartate aminotransferase (AST), alanine aminotransferase (ALT), total protein and total lipid contents in 4th instar larvae, the 2nd instar larvae were treated with the LC₅0 concentration of each extract. Results showed that the two tested extracts caused a significant increase in duration of larval and pupal stages. While, induced a significant decrease in the pupation, adult longevity and fertility. Also, the two tested extracts reduced the activity of AST and ALT enzymes and decreased in content both of total protein and total lipid for 4²¹1arval instar.