Interfacial mechanical properties of single-chamber dual thrust grain were studied by tensile strength equipment, at +50℃ -40℃and 25℃,the tensile intensity and the elongation of propellant with different components,different Treatment method surface and Topology prepared by the techniques were obtained.The tensile failure surface appearance and the element analysis were presented by SEM and XPS at the same time. The results show that the interfacial mechanical properties between the propellants made by screw extruded and casted crafts are higher than that of the casted one, and there is little effect for the deal method and the cohesive structure on the mechanical properties for interfacial surface, moreover, the final mechanical properties of propellants can be attributed to the inferior one.