To constitute a passage switching valve having injection ports by a general passage switching valve.

Six pipe connection ports 27 of a passage switching valve 7 are composed of connection holes 27a having the same structure. The connection holes 27a are uniformly arranged on the same plane to be the upper face of a stator 36. A needle adaptor 42 is inserted into one connection hole 27a by a screw to constitute an injection port 8. By screwing the needle adaptor 42 into the connection hole 27a, a needle 6 inserted into the needle adaptor 42 can be connected to a passage 27b extended from the bottom of the connection hole 27a up to a face opposed to a rotor 32.