A chemical solution vaporization device includes a chemical solution tank including chemical solution vaporization rooms, a chemical solution sensing room, and a chemical solution supply room. A first internal wall separating the plurality of chemical solution vaporization rooms from each other includes a first opening at a lower portion thereof. A second internal wall separating at least one of the plurality of chemical solution vaporization rooms from the chemical solution supply room includes a second opening at a lower portion thereof. A third internal wall separating at least one of the plurality of chemical solution vaporization rooms from the chemical solution sensing room includes a third opening at a lower portion thereof. And a lower portion of a fourth internal wall separating the chemical solution sensing room from the chemical solution supply room is combined with the lower wall.