In recent years, sharing business models have emerged based on the use of technology. Thus, this study used the constructs of UTAUT2 and Network Externalities, in order to analyze how the network externality moderates the acceptance of an app used in peer-to-peer platform. A survey was conducted with 243 Uber users and data were analyzed through the structural equation modeling. As a result, it has been found that all factors influence user acceptance in a positive way. However, the network externality moderates this influence when it comes to factors as facilitating conditions, habit, and social influence.