Abstract: An equilibrium problem of multi-period dynamic closed-loop supply chain network,which comprises manufacturers and demand markets,based on the product's lifetime is studied. Using variational inequality and complementary theory,the optimal conditions for manufacturers and demand markets are formulated,and thus the integrated closed-loop supply chain network equilibrium model is established. The equilibrium is obtained by employing modified project contraction algorithm with fixed step. Using numerical examples,the impacts of different product lifetime and related parameters on the supply chain network equilibrium results are compared and analyzed,and the solution to a critical problem that is encountered while making decisions in the relevant departments of government and manufacturers in a supply chain network is provided. The results of this study can help promote research in other related fields.