In the context of the rapid development and widespread adoption of the Internet, AI customer service has emerged as an inevitable trend to enhance customer service on e-commerce platforms. This paper presents a sample survey of 190 e-commerce platform consumers to investigate the mechanisms underlying the relationship between AI customer service interaction and customer purchase intention during online shopping. The results indicate that: (1) AI customer service interaction significantly reduces customer’s perceived risk; (2) Customer’s perceived risk has a significant negative impact on customer purchase intention; (3) AI customer service interaction has a significant positive impact on customer purchase intention; (4) Customer’s perceived risk mediates the relationship between AI customer service interaction and customer purchase intention; and (5) Platform reputation moderates the relationship between AI customer service interaction and customer’s perceived risk. These findings hold important theoretical and practical implications for understanding the complex interplay between e-commerce AI customer service interaction, customer’s perceived risk, and customer purchase intention, and for improving the effectiveness of AI customer service in e-commerce settings.