The ESD protection device includes: opposed electrodes 2 including an opposed electrode 2a on one side and an opposed electrode 2b on the other side, and a discharge auxiliary electrode 3, the discharge auxiliary electrode being placed so as to extend from the opposed electrode on one side to the opposed electrode on the other side, wherein the discharge auxiliary electrode contains metal grains, semiconductor grains and a glass material, the metal grains, the semiconductor grains, and the metal grain and the semiconductor grain are bound together, respectively, via the glass material, the average grain size X of the metal grains is 1.0 μm or more, and the relationship between the thickness Y of the discharge auxiliary electrode and the average grain size X of the metal grains satisfies the requirement of 0.5≦Y/X≦3.