In view of the foregoing, it is desirable to provide a wiring board improved in reliability of connection involving an electrode pad disposed on a surface of a ceramic insulator layer.

According to one aspect of the present disclosure, a wiring board comprises: an insulator layer composed mainly of ceramic; a conductor extending through the insulator layer in a thickness direction thereof; and an electrode pad disposed on a first surface of the insulator layer and connected electrically with the conductor, wherein: the electrode pad includes through holes extending through the electrode pad in a thickness direction thereof; and each of the through holes is positioned to avoid overlapping with the conductor in the thickness direction of the insulator layer.

The following describes embodiments of the present disclosure, referring to the drawings.