An air conditioner includes at least one compressor, an outlet pipe, an inlet pipe, and at least one bypass pipe. Oil and/or refrigerant discharged from the at least one compressor flows through the outlet pipe. The inlet pipe receives the oil and/or refrigerant flown through the outlet pipe and allows the oil and/or refrigerant to flow to the at least one compressor. The at least one bypass pipe is connected to the at least one compressor and allow bypass flows of the oil and/or refrigerant from the at least one compressor to the outlet pipe.