A simple method for the synthesis of octahydroquinazolinone derivatives in the presence of BF3.SiO2 and Insecticide activity of these compounds against spodoptera litura was investigated to be comparable to commercial pyrethroid insecticides, Cypermethrin and Cyhalothrin. The structure of the isolated compounds was characterized by 1HNMR and FTIR spectroscopy.The proposed method had some advantages such as high yield, mild reaction condition, ease of operation and workup, high product purity and green process.