The invention relates to a method and a device for molding hollow moldings with thin films on inner surfaces. In the method, a fixed mould and a slideable moving mould are adopted, wherein the fixed mould is provided with a deposition groove; and deposition elements such as a target electrode and the like are arranged in the deposition groove. The method comprises the following steps of: executing primary molding for forming a body part and a cover part of which the peripheries of the openings are provided with joint parts; after covering by using the deposition groove, depositing the body part reserved in a vertical sliding mould; aligning and clamping the body part which has been deposited in the mould and the cover part; and injecting molten metal to integrating the joint parts.