Inspired by mussel mucin, polydopamine has attracted widespread attention because of its strong adhesion and excellent carbon yield. In this paper, the main preparation methods of polydopamine coatings, such as dipping method and transfer method, were reviewed, and various influencing factors in the preparation process were analyzed, revealing their influence on the formation rate of polydopamine and thickness of final polydopamine coating. The preparation method, structural properties and application of its derived carbon materials were briefly summarized, and the layered structure and high conductivity similar to graphene have led to its extensive application in frontier fields such as flexible electronics and energy storage.