Evaporative cooling is an energy efficient and environmentally friendly air conditioning technology. Research and application of evaporative cooling in China have been very fruitful; however, they were little known to the world because most of works were published in Chinese. Therefore, this paper intends to present a comprehensive summary on them. The working principles and thermodynamic characteristics of different types of evaporative cooling, including direct, indirect and semi-indirect evaporative cooling, are first introduced. Experimental and theoretical research works on feasibility studies, performance test and optimization as well as heat and mass transfer analysis are then reviewed in detail. The feasibilities of evaporative cooling under different climates, efficiencies of various evaporative cooling equipment, and critical parameters and techniques for improving the efficiencies as well as numerical modeling of evaporative cooling processes are recalled. The typical systems and equipments of evaporative cooling adopted in China are reviewed in Part II.