A compressor that sucks refrigerant gas from an external refrigerant circuit, compresses the sucked refrigerant gas and discharges the compressed refrigerant gas, comprising a cylinder having a plurality of bores, a front housing coupled to the front side of the cylinder and forming a crank chamber, a driving shaft supported so as to freely rotate with respect to the cylinder and the front housing, a single-headed piston connected to a slanting plate element mounted on the driving shaft and linearly reciprocating inside the bores of the cylinder, and a rear housing coupled to and closing the rear side of the cylinder. In the compressor, the rear housing comprises a discharge chamber provided at the center of the interior of the rear housing, so that the refrigerant gas discharged from the cylinder remains in the discharge chamber before being discharged to the external refrigerant circuit, a suction chamber provided so as to surround the discharge chamber, so that refrigerant gas sucked from the external refrigerant circuit remains in the suction chamber before being moved to the cylinder, and a pulsation pressure reduction conduit provided at the rear side of the rear housing, having an inlet led to the discharge chamber and an outlet led to the external refrigerant circuit, and extending in a radial direction of the rear housing, and wherein the inlet of the pulsation pressure reduction conduit through which the discharged gas of the discharge chamber passes is positioned at a distance at which the pressure pulsations of the discharged gas at the respective discharge holes are substantially equal.