Abstract: Coal-fired supercritical carbon dioxide（sCO₂） power generation units have the advantages of high efficiency and flexibility, playing an important role in the transition of China’s traditional thermal power generation from base load to peak load. The sCO₂boiler is a key core component that combines coal-fired power generation with the sCO₂cycle. In order to clarify the technical challengesand their solutions of sCO₂boilers, this paper systematically reviews the research status of sCO₂boilers, summarizes and analyzes the characteristics of solutions to technical challenges, and points out the future research directions for sCO₂boilers. The main findings are as follows: 1) Compared with traditional steam boilers, sCO₂boilers have higher average heat absorption temperatures and higher temperatures on the heating surfaces,which increases the risk of overheating. The mass flow rate of sCO₂boilers is 6 to 8 times that of traditional steam boilers, making it more difficult to decrease the frictional resistance of the heating surfaces. The generation and removal of pollutants in sCO₂boilers have unique characteristics. 2) Numerical simulation methods of heat transfer that couple flue gas and working fluid can be used to optimize the combustion system and the arrangement of heating surfaces, thereby reducing the risk of overheating on the heating surfaces. 3) Parallel arrangement of radiation heating surfaces can significantly reduce the resistance of the boiler, but it also leads to a more complex furnace structure. 4) Currently, there is limited research on pollutant emissions and removal methods for sCO₂boilers, lacking comprehensive studies and feasible solutions. The current research on sCO₂boilers in academia and industry mostly focuses on theoretical analysis and design optimization, with fewer experimental studies and engineering demonstrations. There are issues such as unsatisfactory methods for pressure drop reduction, incomplete understanding of pollutant emissions characteristics and control methods, and a lack of research on flexibility. In order to promote the engineering application of coal-fired sCO₂power generation technology, breakthroughs are needed in the following directions: simple and feasible pressure drop reduction methods, comprehensive understanding of pollutant emission characteristics and control methods, methods for regulating the flexibility and thermal stress, and experimental or engineering demonstrations of sCO₂boilers.