Since 2000,the EU,the US and other developed countries started trying the application of cold ironing system in various types of ports,and even the combination with hybrid ships. China applied the cold ironing system for the first time in 2009. As one of the measures to prevent the air pollution in cities which was included in the “12th five-year plan”,the cold ironing system becomes an important part of building a green and smart port. This article compares the technological application and development of the cold ironing technology in China and abroad in the past 20 years,summarizes the composition and configuration of the cold ironing system,and gives a prediction to the development orientation of the cold ironing technology based on a comprehensive analysis.