PROBLEM TO BE SOLVED: To provide a vacuum molding device capable of making a thickness of a sheet material even when performing draw molding.SOLUTION: A vacuum molding device includes a cavity mold 21 formed with a projection 22 and provided with a main cut blade 23 on the edge surface of the projection 22, and adheres a sheet material to the surface of the cavity mold 21 while forming a hole on the sheet by the main cut blade 23 and applies draw molding to the sheet, by arranging the sheet on the surface of the cavity mold 21 and vacuum suctioning a space between the cavity mold 21 and the sheet. The side surface of the projection 22 is formed with a corner part 22D recessed to the inside of the projection 22 to an edge surface 22C of the projection 22, and the edge surface 22C of the projection 22 is provided near the corner part 22D, with auxiliary cut blades 24 and 25 for forming a hole on the sheet during draw molding. The main cut blade 23 and the auxiliary cut blades 24 and 25 are arranged separately f
