Abstract: Scaling up offshore wind power is of great significance for China to achieve energy transition and dual carbon goals. The reliability issue of offshore wind power is one of the bottlenecks restricting its development. Based on the general topologies of offshore wind power grid integration, this paper reviews the reliability evaluation models and methods, wind power output models, and the application in reliability evaluation of offshore wind turbines, power collection system and clustering transmission system, and summarizes the failure probability and failure repair time of various components of offshore wind power system. With this contribution, the reliability improvement methods of offshore wind power are discussed from the perspective of critical components and system level. Finally, the research direction of offshore wind power reliability is prospected.