The present invention is a method for producing a power module, including processes (1) to (4) in the following order: (1) a disposition process of disposing a thermosetting resin composition that is solid at 25° C. into a container housing an insulator substrate with multiple semiconductor components mounted thereon; (2) a melt process involving disposing the container having the thermosetting resin composition disposed therein into a molding apparatus capable of heating, pressurization, and depressurization, and heating the container to melt the thermosetting resin composition; (3) a pressurization-depressurization process of performing one or more depressurizations and one or more pressurizations inside the molding apparatus; and (4) a cure process of heating the inside of the molding apparatus to cure the thermosetting resin composition. This is to provide a method for producing a power module having few voids at the time of molding and excellent reliability.