Laboratory and greenhouse experiments were conducted to investigate the efficacy of the ntomopathogenic nematodes (EPNs), Steinernema carpocapsae, Heterorhabitis bacteriophora, two insecticides based on Azadirachtin and two Neonicotinoid insecticides. These treatments were applied alone or in combination against the last instar larvae of the black cutworm, Agrotis ipsilon (Hufnagel). The survival rates of S. carpocapsae and H. bacteriophora in the two group of insecticides have ranged between 96.1 to 99.7 after 72 hours of exposure. Data clearly indicated that S. carpocapsae was more virulent against A. ipsilon, whereas H. bacteriophora was less virulent at all concentrations under laboratory conditions. Mortality percentage increased significantly with increasing IJs concentration and time of exposure, reaching up to 100% and 90% at 160 infective juveniles (IJs) concentration, after 72 hours of exposure in S. carpocapsae and H. bacteriophora, respectively. Combination between EPNs at the rate of 80 IJs concentration and either each of the both group of insecticides (Azadirachtin and Neonicotioind) increaseing the efficacy of EPNs and mortality rates of A. ipsilon increased significantly under the laboratory condition. Results proved that S. carpocapsae and H. bacteriophora were less efficient under greenhouse condition when applied in combination with any of the insecticides at 5000 IJs/ 25 ml. EPNs efficacy in combination with Azadirachtin has mostly increased in comparison to EPNs with neonctinoid. This recommended that a mixture of Azadirachtin + EPNs could be applied for an efficient control of A. ipsilon.