It is often difficult to realize effective governance and management within the inherent complexity and uncertainty of disasters. The application of crowdsourcing, through encouraging voluntary support from the general public, advances efficient disaster governance. Twelve international case studies of crowdsourcing and natural disaster governance were collected for in-depth analysis. Influenced by Complex Adaptive System theory, we explored the self-organizing operation mechanisms and self-organization processes of crowdsourcing within disaster governance. The self-organizing operation mechanisms of crowdsourcing are influenced by the multi-directional interaction between the crowdsourcing platform, the initiator (who commences the crowdsourcing process) and the contractor (who undertakes disaster reduction tasks). The benefits of crowdsourcing for governance structure and self-organization processes in natural disaster governance are reflected in three perspectives: strengthening communication and coordination, optimizing emergency decision-making, and improving the ability to learn and adapt. This paper discusses how crowdsourcing can promote disaster resilience from the perspective of the complex adaptive system to enrich the theoretical research on crowdsourcing and disaster resilience.Sustainability 2020, 12, 1862 2 of 14 enhancing community resilience. The research conducted by Baybay and Hindmarsh (2018) in coastal communities in the Philippines shows that community engagement can be increased by improving community activities, knowledge, skills, resources, and by adopting local culture and customs, which are crucial to promoting community resilience [4]. Traditional community engagement refers to offline action processes, while the Internet provides a new form of online community engagement. Crowdsourcing platforms, such as portals, social media, and online applications, have become effective tools for community engagement, by reducing the transaction costs associated with information search, analysis, and decision-making, as well as lowering resource costs (time, money, health, etc.) for civic engagement [5]. Crowdsourcing expands the boundaries of traditional community engagement, which is not limited by time or space, while people from all over the world can participate in specific actions online anytime and anywhere.The issue of how crowdsourcing promotes the self-organization process and builds disaster resilience is understudied. Existing research focuses on how crowdsourcing can be used to collect and analyze disaster data, as well as crowdsourcing's use in communication, loss assessment, and decision support. Research focuses on the functions of crowdsourcing at the technical level, but does not consider the interaction between different subjects in crowdsourcing from the perspective of disaster governance. Taking a tactical emphasis, many studies are based on a single case that focuses on how crowdsourcing can mitigate local problems caused by a specific disaster [6][7][8]. This paper analyses 1...