PURPOSE: To reduce the number of necessary parts and facilitate installation work by constituting valve structure of the pump such as reciprocating compressor, vacuum pump, etc. from a thick part and a thin part which are made of elastic material and formed ingtegrally and fixing said valve structure by the thick part as sealing part.

CONSTITUTION: When a valve 32 is constituted of an intake valve and a discharge valve which are integrally formed, an annular thick part 38 having the form '8' and a lip part 39 constituted of a valve plate and a thin part are formed integrally from the elastic material such as rubber. Said valve 32 is inserted between the head plate 30 and the head cover 33 of a pump, and the parts between the outside of the pump, intake passage 43, and a discharge passage 46 are sealed at a same time by the thick part 38, and the valve 32 is fixed by a fixing screw 34. The intake valve and the discharge valve may be prepared separately.