Ceramic catalyst body

A ceramic catalyst body has a ceramic carrier supporting catalyst therein. The ceramic carrier has plural cells surrounded by plural cell walls arranged in a honeycomb shape, and a catalyst separation ratio H of the ceramic carrier expressed by the following formula is not more than 35%. H=217.254+(−0.167)×T+0.345×D+28.731× CTE−3.343×S, where CTE(×10−6/° C.) is a difference between a thermal expansion coefficient C1 of the ceramic catalyst body and a thermal expansion coefficient C2 of the ceramic carrier, T(K) is an internal temperature of the ceramic carrier, D(cc/g) is a amount of fine pores of not more than 2 μm in the ceramic carrier, and S(%) is a surface porosity indicating the ratio of an area of opening parts of the fine pores on a surface of the ceramic carrier.