Floating nuclear power plant (FNPP) is a movable nuclear power plant built on the floating platform. FNPP belongs to the category of small reactor based on the classification of electric power. It can be used for power generation, desalination, heating, and can satisfy the special needs of regional power supply, regional heating, offshore oil exploration, remote areas, isolated island, and etc. Based on the analysis of the development trend, the characteristics and the advantages of FNPP, this paper summarizes the ACP100S FNPP solutions of China National Nuclear Corporation, and introduces the design principles, technical features, design parameters, overall technical scheme, test and verification, and demonstration project of ACP100S.