The compressor has a differential pressure type flow rate detector that obtains the pressure in an upstream passage and the pressure in a downstream passage to detect a refrigerant flow rate within a refrigerant passage. The detector has an accommodation chamber, and a partition body slidably accommodated within the accommodation chamber. The partition body comparts the accommodation chamber into a high pressure chamber to which the pressure in the upstream passage is introduced, and a low pressure chamber to which the pressure in the downstream passage is introduced. The compressor has an oil separator having an oil introduction passage connected to the oil separating chamber and a high pressure introduction passage introducing the pressure in the upstream passage to the high pressure chamber. The oil introduction passage introduces the oil separated from the refrigerant by the oil separator to a pressure zone other than a discharge pressure zone.