Large and medium-sized hydropower projects, consisting of heavy workload resettlement projects, are the key system engineering that affects the long-term social and regional economy development. The resettlement projects are vital to the process and cost of the whole hydropower projects and to the regional social stability. The rationality of the governance mechanism of resettlement projects in the large and medium-sized hydropower projects is discussed from a stakeholder perspective. By adopting the multidimensional classification method and Mitchell score-based approach, the main stakeholders of resettlement projects in hydropower projects are categorized from three aspects of resources-influence, relationship and sociality. Then determinate, perspective and potential stakeholders of resettlement projects are classified, and their behaviors and risks are summarized. Moreover, the combined structure of internal and external governance of resettlement projects in the large and medium-sized hydropower projects is proposed. Based on the theory of governance, three governance mechanisms of resettlement projects in hydropower projects, including weighting and network consultation mechanism, benefit-share mechanism and motivation and restriction mechanism, are identified so as to lay the theoretical foundation for promoting the implementation of resettlement projects in hydropower projects in China.