Abstract: The significance of nuclear energy as a clean energy source is increasingly prominent. Fast reactor, as the core reactor type of the fourth-generation nuclear energy system, has advantages such as high uranium resource utilization rates, strong nuclear fuel breeding capability, and effective management of radioactive wastes. They are an important part of China’s nuclear energy development strategy. This paper focused on the technological breakthroughs and engineering practices of the reactor control system in China’s high-power fast reactor, introducing the independent innovation of China’s fast reactor technology and the related industrial upgrading. In the research, by independently developing sodium-related instruments (such as permanent magnet sodium flow meters and mutual inductance sodium level meters), multiple key technologies were broken through to achieve domestic production and supply. A simulation model of the main control systems of the plant was established, the control scheme was optimized, and it was successfully applied to the high-power fast reactor project. For the first time in the fast reactor field, full digital technology was applied to complete the design, integration, testing, and verification of the protection system, achieving domestic development. The results show that these technological breakthroughs meet the measurement and control function requirements of the high-power fast reactor under various operating conditions, and enhance the level of automation and system reliability. These achievements not only provide important guarantees for the development of China’s fast reactor technology, but also lay a solid foundation for the industrial upgrading and commercial promotion of nuclear energy technology.