Abstract: In view of the retailer's inventory constraints, the consumer arrival process obeying the Poisson distribution, and its purchasing behavior depending on the ability to pay and perceived value, a research is conducted on the optimal consumer credit policy decision of the retailer under different inventory levels in a sales season: never implement, always implement or implement on time. Studies have shown that consumer credit policies should never be implemented when fixed costs are above a certain threshold or when inventory levels are below a certain threshold. When the inventory level is above a certain threshold, the consumer credit policy should always be implemented. When the inventory level is between the above two thresholds, the consumer credit policy should be implemented at the right time, that is, consumer credit should be implemented from a certain moment after the start of the sales season. When the retail price is relatively high, consumer credit subsidies should be provided to consumers. Under other conditions, the shorter the sales season, the more the consumer credit policy should be implemented. Finally, the accuracy and reliability of the proposition are verified by a case study.

Key words: compound Poisson process, inventory constraint, consumer credit