Provided is a molding device for manufacturing a molded product having an arc-shaped bent inner space, wherein the molding device includes: a pair of molds which is joinable to each other and separable from each other, and is capable of forming a cavity C which has a shape corresponding to an outer shape of the molded product in a joined state during molding; a core which has a shape corresponding to an inner shape of the molded product, and is disposed in the inside of the cavity C which the pair of molds forms during molding; and a rotation member which is joined to a terminal end of the core, and is rotatable together with the core after molding. Compared to a conventional molding device, the molding device of the present invention becomes a molding device capable of suppressing the occurrence of a defect on a molded product having an arc-shaped bent inner space at the time of taking out the molded product.