Abstract:A quantitative approach to the comprehensive evaluation of the sustainability of small hydropower in countries along “the Belt and Road” is not established at present. The understanding of the overall level of small hydropower (SHP) development in related countries is not clear enough, and it is not conducive to Chinese SHP participation in “the Belt and Road” initiative. In this study, taking countries along the “the Belt and Road” as the research objects, based on the categories of economy, politics, society, ecological environment and resources, the indicators system of small hydropower sustainability is built. Based on this, an analytic hierarchy process (AHP) and fuzzy comprehensive evaluation model is adopted to calculate and analyze the sustainability of small hydropower in relevant countries from a quantitative perspective. Key regions for China’s small hydropower to participate in “the Belt and Road” Initiative are indicated, including the seven countries in Southeast Asia, one country in East Asia, and six countries in South Asia; economy, society and resources factors are the main restrictions for the development of small hydropower. Secondary indicators which should be focused on, are also put forward. Based on our results, some policy suggestions are proposed from the perspectives of top design, new development mode, investment and financing, green development ideas, evaluation indicator system, and risk prevention.