A circuit board includes an electric circuit having a wiring section and a pad section in the surface of an insulating base substrate. The electric circuit is configured such that a conductor is embedded in a circuit recess formed in the surface of the insulating base substrate, and the surface roughness of the conductor is different in the wiring section and the pad section of the electric circuit. In this case, it is preferable that the surface roughness of the conductor in the pad section is greater than the surface roughness of the conductor in the wiring section.