An ESD protection device includes a ceramic multilayer board, a cavity
disposed in the ceramic multilayer board, at least one pair of discharge
electrodes having ends, edges of the ends being opposed to each other at
a predetermined distance in the cavity, and external electrodes disposed
on outer surfaces the ceramic multilayer board and connected to the
discharge electrodes. The ceramic multilayer board includes a composite
portion, which is disposed in the vicinity of the surface on which the
discharge electrodes are disposed and is at least disposed adjacent to
the opposed ends of the discharge electrodes and to a space between the
opposed ends. The composite portion includes a metal material and a
ceramic material.