An IC module is provided that includes an IC having a terminal electrode, and a substrate having a first surface and a second surface opposite to each other and having a land formed on the first surface. Moreover, the land is connected to the terminal electrode of the IC. On the first surface of the substrate, an insulator layer that covers an area outside of a formation area of the land is formed. A difference between a thickness of the insulator layer and a thickness of the IC is smaller than a difference between the thickness of the insulator layer and a thickness of the substrate, and the thickness of the substrate is smaller than the thickness of the insulator layer.