Abstract: This paper introduces a cutterhead central valve block assembly of a roadheader used for tunnel excavation in tunnel construction, and discusses the component composition and design characteristics of the cutterhead central valve block assembly and its assembly with the cutterhead and center rotary joint Connection method and working principle. Practice has proved that as the central rotary joint and cutter disc transition connecting part, the central valve block assembly lubricates and retracts the cutter disc copying knife, wear detection, accurate monitoring of tool wear,smooth work of cutter head mud and foam injection port Provide strong guarantees.