A communication module includes a filter element, a package substrate on which the filter element is mounted, and a module substrate on which the package substrate is mounted. Each of the package substrate and the module substrate is formed of a laminate of a plurality of metal layers and a plurality of insulation layers. An outermost insulation layer forming a mounting surface of the package substrate that is a surface on which the filter element is mounted has a thickness smaller than a thickness of at least one of the other insulation layers included in the package substrate. An outer insulation layer forming a mounting surface of the module substrate that is a surface on which the package substrate is mounted has a thickness smaller than a thickness of at least one of the other insulation layers included in the module substrate.