A variable capacity type compressor has a swash plate (16), pistons reciprocating in the cylinder bores, a suction chamber (7a), and a discharge chamber (7b) with a check valve (33) downstream. The check valve (33) has a valve element (72) arranged in the case (71) for cooperation with the valve seat (70). The case (71) flow passage through the communication hole (71b) to the outside circuit. The communication hole (71b) is shaped in a triangular shape so that its opening area is smaller than that of a communication hole of a check valve opening area is proportional to a valve lift.