Abstract: From the perspective of spillover effect, this paper studies the carbon emission reduction investment strategy between upstream and downstream enterprises in the supply chain, and uses the evolutionary game model and the system dynamics model to explore the strategic choices of various stakeholders in the supply chain for carbon emission reduction in the context of low carbon economy and a stable path to evolution. The results show that the steady state of upstream and downstream enterprises’ decision to invest in carbon emission reduction is closely related to factors such as the cost and benefits of emission reduction, the compensation cost of " free-riding” behavior and the additional benefits obtained. The researchers further explored the evolution process based on the reward and punishment mechanism under government regulation, and analyzed the impact of the amount and proportion of rewards and punishments on the evolutionary stability strategy. Finally, the effectiveness of the evolution model is verified by the simulation analysis of system dynamics software.