Abstract: A swash plate type compressor is provided with a front and rear cylinder blocks having a crank case connected to a suction port. The cylinder blocks include a plurality of cylinders, and are connected to a front and rear housing sections for covering the cylinders. Each housing section contains a discharge chamber. A drive shaft is rotatabley supported by the cylinder blocks. A swash plate is mounted on the drive shaft and is rotatably disposed within the crank case. Two-head pistons move within their respective cylinders in cooperation with the swash plate. The refrigerant is drawn into, and compressed in each cylinder. Thereafter, it is discharged into the external refrigerating circuit through the front and rear discharge chambers, and a final discharge port. A discharge passage includes a hollow primary passage which is provided within the drive shaft. The primary passage communicates with the front and rear discharge chambers. A groove is provided on an inner wall of the primary passage.