Providing authenticity insurance services for consumers on online platforms can effectively solve the problem of fake goods in online shopping and improve consumers' purchase intention. Based on the supply chain structure composed of brand suppliers and online platforms, this paper takes brand suppliers and online platforms as the main bodies respectively under the influence of fake goods, establishes two decision models before and after the platform joins the authenticity guarantee insurance under different channel modes, considers that the cooperation mode between the platform and insurance companies is fixed insurance commission, compares different modes, obtains the optimal pricing, demand and profit, and analyzes the impact of adding authenticity guarantee insurance services on the supply chain and the channel mode preferences of supply chain members under different situations.