Based on the Debye mode,electron gas model,and Gruneisen equation of sate,new formula were deduced which describe the individual contributions of lattice vibration and hot electron to shock temperature,shock pressure and compression volume of porous metals.It is found that the contribution of lattice vibration to shock compression volume accord with W-J equation;meanwhile,the contribution of hot electron to shock compression volume also can be calculated by the improved equation.In this paper,we especially discussed the reliability and the physical meaning of the new equations.