A four-parameter equation of state (EOS), expressed in terms of the equilibrium volume V 0 , cohesion energy E C , isothermal bulk modulus B 0 and its first pressure derivative B′0, is proposed and proved to performance better for 40 selected metals than the well-known Rose and Vinet equations. Based on the proposed EOS, the thermal expansions α, melting points T M , ultimate strengths P C and critical volume V C are calculated, and interestingly, a unique correlation is observed for all the studied metals, i.e. PC/B0(VC−V0)/V0≈0.31. It turns out that the calculated results are in good agreement with the experimental observations.