To smoothly iron a suit of clothes having a projection such as a button and to prevent damage of an expensive button and the like.

A groove 3 is made in an ironing board 1, and the groove 3 is filled with a cushioning material 4. A suit of washed clothes such as a shirt is put on the ironing board 1 with its backside up and a button 7 is positioned in the groove 3. When the suit of clothes is pressed by an iron 6 from the upper side, the button 7 is dropped because of the cushioning material 4 and the suit of clothes is flattened and ironed smoothly. A line 2 is applied to a cover 5 over the groove 3 because the groove 3 is not easily recognizable when the ironing board is covered with the cover 5. In ironing, the button 7 is positioned on the line 2. The button is prevented from damage because the iron is not brought into direct contact with the button, and texture of the clothes is not deteriorated as the clothes is ironed with the back side up.