This paper studies the decision-making of poverty alleviation investment in the supply chain system composed of agricultural suppliers and e-commerce sales platforms. Using the method of differential games, the changes of the equilibrium results of supply chain members in two cases are investigated and compared. The research shows that Under the Nash non-cooperative game situation, government subsidies can improve the degree of poverty alleviation efforts and the optimal benefits of supply chain members. The government subsidy coefficient τ only affects the poverty alleviation efforts and total revenue of agricultural suppliers and e-commerce sales platforms, and has no effect on the promotion efforts of e-commerce sales platforms.