To obtain a rotating valve in which a liquid contact area is reduced, which prevents a contamination and which reduces a frictional resistance, by a method wherein one each of openings which are formed in the central part and the peripheral part of a rotor are constituted in such a way that they communicate at the inside and the outside of the rotor.

A rotating valve 1 which is used to change over a plurality of pipe flow passages for liquid chromatography is constituted of a stator 2 in which one center through hole 21 is formed in the center and in which a plurality of peripheral- part through boles 22 are formed in the periphery and of a rotor 3 in which one each of openings are formed in the center and in the periphery. The respective openings in the rotor 3 form both ends of a communication passage 31 at the inside of the rotor 3. The center through hole 21 and one out of the peripheral-part through holes 22 are connected by the communication passage 31. According to the rotation of the rotor 3, the peripheral-part through holes 22 which are connected are changed over. By this constitution, the opposite face of the stator 2 to the rotor 3 becomes annular, the area of a liquid contact zone is reduced, and the friction of the rotating valve 1 is low when the valve is turned. Through holes may be formed in the rotor 3 so as to be connected by a U-shaped pipe.