Based on the operating data of 410 P2P network lending platforms in China， this article takes the regulatory policy promulgated in 2017 as an entry point to explore the impact of regulatory policies on investor confidence， platform competitiveness， and the intrinsic relationship between them in the context of policy uncertainty. This paper uses panel regression， threshold regression， quantile regression， systematic GMM and differential GMM model to explore this issue. The results show that policy heterogeneity has significant differentiation characteristics on the competitiveness of investors and platforms and the internal relationship between them. Further research shows： In the face of uncertain industry risks， new investors are more sensitive and old investors are more stable， both of which have strong liquidity preferences; Industry regulatory policies have a significant effect on the improvement of platform competitiveness; There is a two-way causal relationship between platform competitiveness and investment confidence， but under the impact of industry regulatory policies， the two-way causal relationship between old investor investment confidence and platform competitiveness is more stable.