Provided in the invention is a central rotary joint for a shield tunneling machine. The central rotary joint comprises a housing having a through hole and a rotating shaft inserted into the through hole of the housing. A plurality of medium channels are arranged on the rotating shaft; connecting through holes are formed along an axial direction of the rotating shaft; and medium grooves are formed in the through hole. A pipeline interface is arranged on the housing. Inner sealing structures are arranged on through hole. Each inner sealing structure includes two sealing slots, a lubricating oil slot, and lip type sealing elements; grease injection ports communicated with the lubricating oil slots are arranged on the housing; pressure-bearing lip openings of the lip type sealing elements are opposite to the lubricating oil slots. The lip type sealing elements are installed in the sealing slots. Because the lubricating oil slots are arranged between the adjacent lip type sealing elements, the sealing elements are lubricated and certain pressures are provided to squeeze out worn particles, so that a lubricating problem of a non-oil mediums during the sealing process can be solved and the sealing time of pollutants containing solid particles is prolonged. On the basis of the scheme, the sealing time can be prolonged effectively and the joint with the simple structure can be realized easily.