The modified single-based propellant was prepared by the "impregnated-deterred-coated" technology.The combustion and interior ballistic performances of the propellant were investigated by closed-bomb and 857-30 mm gun.The structure of the modified single-based propellant was analyzed.The results show that in comparison with conventional single-based propellant, the muzzle velocity of modified single-based propellant increases by 5% at least at normal, high and low temperatures.The modified single-based propellant has the characteristics of low temperature coefficient when used in the 857-30 mm gun.It is resulted from the formation of the zipper structure with end sealing and the softness of the body surface.