Abstract: Aiming at the secondary supply chain composed of a manufacturer and an e-commerce platform, considering that a bank provides credit card service to some customers, the consumer credit service strategy of the e-commerce platform under wholesale mode and agency mode and the conditions for launching consumer credit service is studied. It is found that whether in wholesale mode or agency mode, the launch of consumer credit on the platform will increase the retail price of the product and expand the market demand at the same time. In the agency mode, when the bad debt risk of consumer credit and the platform commission rate are low, the platform will launch a consumer credit service. At this time, platform credit service and bank credit card service are not exactly a competitive relationship. The platform, the manufacturer and the bank can achieve a win-win-win situation, but the bank needs to take measures to prevent consumers from switching to platform consumer credit service. In the wholesale mode, when the bad debt risk is low, the platform provides consumer credit service. At this time, the profit of the bank will be reduced, and the impact on the profit of the manufacturer is related to the bad debt risk. When the bad debt risk is extremely low, the manufacturer and the platform can achieve win-win cooperation. In both modes, the bad debt risk does not affect the retail price but has an important impact on whether the platform will launch consumer credit. Therefore, how to control consumer credit risk is an important issue.

Key words: consumer credit, wholesale mode, agency mode, e-commerce platform