Abstract: The distributed control system (DCS) of 10 MW High-Temperature Gas-cooled Reactor (HTR-10) takes charge of operation monitoring and control to HTR-10. The disadvantages of the original DCS at present such as reliability of facilities and history operation data system were introduced. Based on the requirements of technologic systems and control objects, the system architecture, functions and performances were analyzed. The I/O channels configuration was completed. The design scheme which was comprised of the multi-redundancy hardware flat based on Schnieder Quantum 67160 series products, the system software flat by UNITY and the configuration tool by iFIX were presented. The control rods and fuel handling control systems were driven by PTO modules. The AC sampling scheme was modified by adopting intelligent instrument. A specified logical gateway for third-party communication will be developed. The design scheme present in this article can solve the problems and match the demands from DCS of HTR-10.