A steam generating device (1) is provided with a metal housing (2), a water supply opening (3) for supplying water into the housing (2), a steam generating heater (4) embedded in the lower part of the housing (2) and evaporating the water supplied from the water supply opening (3), a steam temperature raising heater (5) provided above the steam generating heater (4) with a predetermined distance from an inner wall of the housing (2) and raising the temperature of the steam generated by the steam generating heater (4), and a discharge opening (8) for discharging the superheated steam generated by the steam temperature raising heater (5).