Research of reliability of engineering structures has experienced a developing history for more than 90 years.However,the problem of how to resolve the global reliability of structural systems still remains open,especially the problem of the combinatorial explosion and the challenge of correlation between failure modes.Benefiting from the research of probability density evolution theory in recent years,the physics-based system reliability researches open a new way for bypassing this dilemma.The present paper introduces the theoretical foundation of probability density evolution method in view of a broad background,whereby a probability density evolution equation for probability dissipative system is deduced.In conjunction of physical equations and structural failure criteria,a general engineering reliability analysis frame is then presented.For illustrative purposes,several cases are studied which prove the value of the proposed engineering reliability analysis method.