Abstract: Renewable energy dominated hydropower, wind and solar power has achieved unprecedented development in the past two decades. In the future, it will be the core component of China's clean and low-carbon energy system and the realistic choice to fulfill the carbon emission reduction commitment. This study analyzed the development of clean energy power generation in China and the typical practical projects of hydropower-wind-solar complementary system. Key problems of generation scheduling in complementary system were summarized, i.e., how to participate in the operation for large-scale wind and solar power plants, how to describe the intermittent spatial-temporal generation characteristics, and how to coordinate wind and solar power plants and hydropower plants on the long-term and short-term operations? In view of these problems, the coordination methods and characteristics of hydropower-wind-solar complementary research works were systematically reviewed. Moreover, the technical realization process were expounded in terms of the cluster of wind and solar power plants, the description of cluster generation, the modeling and solution of long-term and short-term coordination of hydropower- wind-solar complementary system. We hope that the developed methods can provide practical and available technical means for actual operations of China's multi-energy complementary projects, and help to achieve the goal of "carbon peak, carbon neutralization".