The invention relates to a method for improving interface bonding performance of an EPDM (ethylene prophlenediene monomer) heat insulating layer, an HTPB (hydroxyl-terminated polybutadiene) lining and an NEPE (nitrate ester plasticized polyether propellant). The method includes that the HTPB lining coated on the surface of the EPDM heat insulating layer in an engine is controlled to be in the thickness from 0.7mm to 1.5mm, so that the purpose of remarkably improving the interface bonding performance of the EPDM insulating layer, the HTPB lining and the NEPE propulsive agent is achieved by controlling the thickness of the HTPB lining and on the basis of not changing the lining, propulsive agent formulation and implementation process. The method is simple in process, easy to implement and highly practical.