To manufacture a decorative molded article with a high forming position accuracy of a decoration pattern layer.

A mold 25 that includes a cavity mold 36 and a core mold 26 is used. A film 20 that is provided by forming a decoration pattern layer 14 on a base material film 21 is positioned to the cavity mold 36 in the mold 25 of a mold open state. The film 20 is maintained in the sealed state surrounding a molding surface 38 in an end face 36A of a core mold 26 side of the cavity mold 36. In mold clamping of the mold 25, the film 20 is adhered to the molding surface 38 by vacuum suction, after pushing the film 20 to the cavity mold 36 side and bringing it close to the molding surface 38 by the core surface 31 of the core mold 26. Afterwards, a decorative molded article that is decorated in the design surface of the molded article body by a decoration pattern layer 14 is obtained by attaching the decoration pattern layer 14 of film 20 on the design surface of the molded article body, while forming the molded article body by injecting the molten resin into a cavity 41 formed between the film 20 and the core surface 31 of the core mold 26.