Abstract: Industry self-regulation is an important part of the governance of violations of P2P online loan platforms under the background of "strong supervision" by the government. In order to reveal the behavior strategy relationship and dynamic evolution mechanism among the online lending market entities under the industry self-regulatory mechanism, atrilateral evolutionary game model of behavior strategy including self-regulatory supervision platform, online loan platform and platform customer is constructed. The evolutionary path of the tripartite agent's behavior strategy and its joint action law are analyzed, and then the equilibrium state of model system evolution and the influence of key factors under different constraints are discussed in conjunction with numerical simulation. The findings show that the willingness of the online loan platform to operate in compliance will be strengthened with the increase of incentive level, image effects, customer churn, and industry crisis risks. If the online loan platform has a more complete operation mechanism, or a better reputation, or a larger customer scale, it will be easier to implement self-regulation based on the market approach. The penalties for violations, the benefits of image effects and the sensitivity of the platform’s customers’ regulatory strategies will directly affect the tendency of compliance operation of the online loan platform. Finally, governance measures such as increasing the punishment of illegal platforms, strengthening platform information disclosure and brand image construction, and guiding both borrowers and lenders to choose platforms rationally are put forward combined with the results of simulation analysis.

Key words: industry self-discipline; P2P lending platform; violation governance; evolutionary game