To provide a reciprocating compressor, having a locking recessed part formed in the peripheral wall of the end part on a valve plate side of a bore to regulate the opening of an inlet valve, and preventing self-excited vibration of the inlet valve when the compressor is operated with a small capacity.

This reciprocating compressor includes: a cylinder block where the bore is formed; a rotating shaft driven to rotate by an external driving source; a piston reciprocating in the bore following the rotation of the rotating shaft; the valve plate where an inlet hole and a discharge opening opposite to the bore; and a cylinder head holding the valve plate provided with an inlet valve and a discharge valve in cooperation with the cylinder block and demarcating an inlet chamber communicated with the inlet hole and a discharge chamber communicated with the discharge opening, wherein the peripheral wall of the end part on the valve plate side of the bore is provided with the locking recessed part for regulating the opening of the inlet valve. An opening having a smaller diameter than the inlet hole opposite to the inlet hole of the valve plate is formed in the inlet valve, and an auxiliary inlet valve abutting on the inlet valve is provided to cover the opening on the side isolated from the valve plate, and the bending rigidity of the auxiliary inlet valve is set to a value smaller than the bending rigidity of the inlet valve.