In a seat air conditioning unit, a first blower is mounted to a seat cushion and a second blower is mounted to a seat back such that a suction port of the second blower is located on a rear side of the seat back. A duct is provided for leading air blown by the first blower toward the suction port of the second blower. Further, a Peltier module is provided in the duct. A first end of the duct is connected to a discharge portion of the first blower and a second end of the duct defines a duct opening. The duct opening is disposed to open at a position adjacent to the suction port so that a volume of air sucked in the suction port is larger than a volume of air discharged from the duct opening toward the suction port.