It is aimed to enhance compressor efficiency by both reducing an amplitude of pressure pulsations and reducing pressure losses in a discharge muffler space into which is discharged a refrigerant compressed at a compression unit. A low-stage discharge muffler space (31) is formed in the shape of a ring around a drive shaft (6). In the low-stage discharge muffler space (31), a discharge port rear guide is provided in the proximity of a discharge port (16) through which is discharged the refrigerant compressed by a low-stage compression unit (10). The discharge port rear guide is provided at a flow path in one direction out of two flow paths from the discharge port (16) to a communication port (34) in different directions around the drive shaft (6), and prevents the refrigerant from flowing in that direction, thereby causing the refrigerant to circulate in a forward direction in the ring-shaped discharge muffler space.