Abstract: High-density energy input and management are becoming the key foundation for reliable and long-life service of future equipment. Thermal management components with microchannel structures have compact structure, small overall size, and high heat transfer efficiency, can well solve the problem of high energy density thermal management and have broad application prospects in aerospace and military fields. The influence of different types of microchannel structures on the heat transfer performance of microchannel heat exchangers is introduced, and the advantages and disadvantages of the traditional micron-level subtractive processing technology and additive manufacturing process for preparing thermal management components with complex microchannel structures are reviewed. The application of stacked additive manufacturing technology in processing thermal management components with complex microchannel structures is described mainly from chemical etching and diffusion welding.