Considering the protection of the ecological environment and the rational utilization of social resources, it is urgent to introduce and promote the shore-to-ship power technology. Firstly, it introduces the disadvantages of the traditional fuel power supply mode of ships in port, presents the advantages of the green shore power supply mode, and briefly describe and analyzes the development and trend of the marine shore power technology both at home and abroad. Secondly, it introduces and analyzes the concept, classification and comparison of the shore power supply system, as well as the power supply mode and the basic principles of the shore-to-ship power supply system. Then, it studies the basic design and the key technologies of the shore-to-ship power supply system. It also introduces the design scheme and the key points of the shore-to-ship power supply system for a 2 500 TEU container ship built in Jinling Shipyard, comparing with various indexes of different power supply modes. Finally, it explains the operation process of the power management for the 2 500 TEU container ship to implement the grid connection between the shore power and the generator set.