Abstract: High-entropy alloys (HEAs) exhibit the outstanding properties, owing to the multi-principal-element design and high-entropy effects. Nevertheless, the conventional forming processes of HEAs fail to produce the complex shapes while maintaining the microstructural uniformity, hindering the industrial application. Additive manufacturing (AM) provides the revolutionary solution for complex component forming and microstructure precision control. The research status of mainstream additive manufacturing technologies used for high-entropy alloy preparation was systematically reviewed in this paper, such as laser powder bed melting and directional energy deposition. The typical systems, microstructure characteristics, mechanical properties, and functional properties of additive manufacturing high-entropy alloys were summarized. The AM technology can refine grains, inhibit harmful phases, promote the formation of metastable phases, and significantly improve material properties through rapid solidification and thermal cycling. However, the challenges still remain, such as complex process parameters, crack sensitivity, high preparation cost, and insufficient multi-scale simulation. In the future, the machine learning should be actively used to optimize the process-organization-performance relationship, develop new AM technology and post-treatment process, design low-cost alloy system, and realize the intelligent design combined with cross-scale simulation.