China is rich in offshore wind power resources, and these resources can be locally consumed by the economically developed provinces located in the eastern coastal region. The development of offshore wind power can accelerate the energy transition in China and help achieve carbon peak in 2030 and carbon neutrality in 2060. In this article, we analyze the current situation, trends, and challenges of energy development in China, and propose that the development of offshore wind power is an important strategic support for the energy structure transformation in China. The key technologies of offshore wind power development in China are summarized including wind turbine, offshore power transmission, offshore engineering, and operation and maintenance technologies. In view of the bottleneck problems restricting the development of China’s offshore wind power industry, we propose some countermeasures and suggestions to promote the healthy and orderly development of China’s offshore wind power industry from five aspects: exploration and evaluation of offshore wind power resources, understanding of energy transition, overall planning and integrated planning, scientific and technological innovation, and policy support mechanism.