A variable displacement swash plate compressor comprising: a cylinder block in which plural cylinder bores are formed, a front housing assembled to the front side of the cylinder block to define a crank chamber, a rear housing attached to the rear side of the cylinder block, in which a suction chamber and a discharge chamber are formed, pistons arranged in respective cylinder bores of the cylinder block so as to reciprocate, a shaft supported by the front housing and the cylinder block so as to rotate freely, a swash plate rotating integrally with the shaft and attached to the shaft so that a tilt angle is variable, and shoes interposed between a peripheral edge portion of the swash plate and the pistons so as to slide, converting a rotating motion of the swash plate into a reciprocating motion of the pistons, in which a supply passage allowing the discharge chamber to communicate with the crank chamber and an release passage allowing the crank chamber to communicate with the suction chamber are provided for controlling a pressure in the crank chamber to control the tilt angle of the swash plate with respect to the shaft, part of the release passage is formed by an oil separation passage formed in the shaft, and the oil separation passage is configured by including a shaft hole extended in an axial direction from a rear end to a front end of the shaft and a side hole extended in a radial direction and communicating with the shaft hole as well as opening to the crank chamber, characterized in that the supply passage is configured by including a through hole formed in the cylinder block so that the through hole opens at a region opposed to the swash plate, and a bypass passage allowing the crank chamber to constantly communicate with the suction chamber is provided separately from the release passage, and wherein a region of the bypass passage communicating with the crank chamber is positioned in an outer side of a rotation trajectory of the swash plate in the radial direction,and wherein the bypass passage communicates with the crank chamber by using part or whole of a bolt hole formed in the cylinder block for inserting a bolt which fastens the cylinder block to the housings (3, 5) in the axial direction. a cylinder block in which plural cylinder bores are formed, a front housing assembled to the front side of the cylinder block to define a crank chamber, a rear housing attached to the rear side of the cylinder block, in which a suction chamber and a discharge chamber are formed, pistons arranged in respective cylinder bores of the cylinder block so as to reciprocate, a shaft supported by the front housing and the cylinder block so as to rotate freely, a swash plate rotating integrally with the shaft and attached to the shaft so that a tilt angle is variable, and shoes interposed between a peripheral edge portion of the swash plate and the pistons so as to slide, converting a rotating motion of the swash plate into a reciprocating motion of the pistons, in which a supply passage allowing the discharge chamber to communicate with the crank chamber and an release passage allowing the crank chamber to communicate with the suction chamber are provided for controlling a pressure in the crank chamber to control the tilt angle of the swash plate with respect to the shaft, part of the release passage is formed by an oil separation passage formed in the shaft, and the oil separation passage is configured by including a shaft hole extended in an axial direction from a rear end to a front end of the shaft and a side hole extended in a radial direction and communicating with the shaft hole as well as opening to the crank chamber, characterized in that the supply passage is configured by including a through hole formed in the cylinder block so that the through hole opens at a region opposed to the swash plate, and a bypass passage allowing the crank chamber to constantly communicate with the suction chamber is provided separately from the release passage, and wherein a region of the bypass passage communicating with the crank chamber is positioned in an outer side of a rotation trajectory of the swash plate in the radial direction,and wherein the bypass passage communicates with the crank chamber by using part or whole of a bolt hole formed in the cylinder block for inserting a bolt which fastens the cylinder block to the housings (3, 5) in the axial direction.