An exhaust gas purification catalyst device comprising a base material and a catalyst coating layer provided on the base material, wherein the catalyst coating layer contains zeolite particles, inorganic oxide particles other than the zeolite particles, and a catalyst precious metal, and the ratio d ZEO /d OX between the average particle diameter D ZEO of the zeolite particles and the average particle diameter dox of the inorganic oxide particles other than the zeolite particles is 3.4 or less.