Ignition occurs under friction is one of the important reasons that lead to accidental explosion of pyrotechnic propellant. And the dynamic friction coefficient is a key parameter on determining the energy obtained through friction. A new method for calculating the dynamic friction coefficient is presented. The method combines the physical model of friction sensitivity tester with theoretical modeling and numerical calculations. The dynamic friction coefficient of black powder and expired single-base propellant are measured based on this method and experimental study. Meanwhile the effects of different experiment conditions on dynamic friction coefficient of both the propellants are discussed. The results show that the dynamic friction coefficients of both the propellants are a range value. With the increase of pressure and sliding velocity, the dynamic friction coefficients of both the propellants vary in some degree. Also the dynamic friction coefficient of black powder is greater than expired single-base propellant.