Infection by entomopathogen nematodes (EPN) occurs by an infectious juvenile that establishes itself in the body cavity of an insect and suppresses the immune response of the insect. Temperature variations and desiccation are the main abiotic factors affecting EPN survival, and UV light destroys EPNs more quickly than chemical insecticides. Spraying directly on the soil surface is the most powerful strategy for applying EPNs. IJs enter the insect body through natural pores and produce hydrolytic enzymes. Entomopathogenic nematodes (EPNs) have been shown to have a variety of impacts on insect immunology, including the destruction of hemocytes, the destruction of proteins that recognize nematodes, and the disruption of prophenoloxidase activation. The mode of action of bacteria inside the nematodes has been discovered through extensive Bt strain screening and cry gene sequencing. Cry proteins can enter nematodes through the stylet and create lytic holes in their cell membranes. LPS has an antagonistic action against nematodes.