With global warming,it is of strategic importance to explore determinants of renewable energy(RE)policy adoption in developing countries. Selecting 176 renewable energy policies in 32 developing countries of the Silk Road Economic Belt(SREB)from 2000 to 2015 and choosing 23 indicators from six systems based on internal and external perspectives,we analyzed and compared differences of determinants in different types of RE policy adoption using panel data logit modeling. We focused on the determinants of four types of RE policy adopted most during the last 16 years. We tested the robustness of the study by adding control variables,replacing variables and using a different model. We found that from a domestic perspective,economic conditions and energy reserves are important determinants for RE policy adoption in developing countries of the SREB. The larger and the richer the country is,the more RE resources the country has,the more likely that a government will promote development of RE by adopting different types of RE policy. From an international perspective,a policy's international vertical diffusion effects contribute more to RE policy'adoption in developing countries of the SREB. Different types of RE policies are influenced by different domestic and international factors. Governments should be highly sensitive to policy guidance from international organizations and major developed countries. With development of the Belt and Road Initiative,China should analyze the target country's energy reserves and economic conditions and focus on the specific nature of the policy. This study provides a scientific foundation and another angle from which to understand determinants influencing RE policy adoption in developing countries.