Abstract: In the buy-back guarantee situation, this paper adopts dual Stackelberg game, on the basis of analyzing the contagion mechanism of associated credit risk in a two echelon supply chain composed of a supplier and a retailer, constructs the basic model and derivative model to study the internal contagion and spillover effects of associated credit risk in the supply chain. Numerical analysis results show that contagion effect of associated credit risk in supply chain has trigger thresholds, and when contagion effect occurs, buy-back rate, loan interest rates and production cost have a positive impact on the contagion effects; while the market price of products has a negative impact on the contagion effect. On the other hand, buy-back rate weakens the positive spillover effect of associated credit risk. The research of this paper has important theoretical and practical significance for risk control of supply chain enterprises and loan institutions.

Key words: supply chain, buy-back guarantee, associated credit risk, contagion effect, spillover effect