Trust is considered to be one of the key factors influencing the sustainable development of the sharing economy. In this paper, we focus on the trust issue of peer-to-peer accommodation models like Airbnb and Xiaozhu, which are among the most common examples of a sharing economy. This research divides trust into two types from the perspective of an accommodation provider in the context of peer-to-peer accommodation sharing: trust in the sharing platform and trust in consumers. The purpose of this paper is to provide a comprehensive view of how the three types of online trust-building mechanisms affect providers’ trust in the sharing platform and trust in consumers. The structural equation modelling with partial least square method was used to empirically test the influence of the online trust-building mechanisms of a sharing economy platform on provider’s trust in the platform and provider’s trust in consumers, based on a sample of 209 providers on online short-term rental platforms in China. The empirical results show that perceived personal safety mechanisms, perceived property safety mechanisms, and perceived review mechanisms are positively related to a provider’s trust in the platform. Provider’s trust in the platform has a positive effect on trust in consumers, while perceived personal safety and review mechanisms have a positive effect on provider’s trust in consumers by the mediation of trust in the platform. This study has theoretical and practical significance for the promotion of the research and development of trust mechanisms in the sharing economy.