none Enter Laboratory experiments were made to evaluate the effect of the bioinsecticide, Radical (Methylamineavermectin) was studied on 2nd, 3rd and 4th larval instars of the cutworm Agrotis ipsilon (Hufn.). The LC50 values of the tested compound were, (40.54, 51.23 and 63.39 ppm after 24 hours) and (33.46, 44.31 and 51.89 ppm after 48 hours) for 2nd, 3rd and 4th larval instars of A. ipsilon, respectively. LT50 values were shortened by increasing the concentrations of Radical. In addition, the side effect of Radical on the parasitoid Apanteles ruficrus Hal. a common parasitoid of the pest was also tested. Obtained data showed that, males were more susceptible than females at the same age. Also, comparing the oral toxicity of Radical, it was found that the LC50 values against the (5-days old) A. ruficrus males and females were about half of those males and females of 1-day old.