A piston-type compressor includes a cylinder block having cylinder bores and a rear housing having a separating wall to divide the interior of the rear housing into a suction chamber and a discharge chamber. Pistons are arranged in the cylinder bores to reciprocate therein. Bolts are inserted in the cylinder block and extend into the separating wall of the rear housing to connect the cylinder block and the housing together. Since the separating wall is forced to the cylinder block by the bolts, no leakage occurs between the suction chamber and the discharge chamber.