A catalyst protection device includes: a catalyst provided in an exhaust system of an internal combustion engine; a bed temperature acquisition unit that acquires a bed temperature for each of a plurality of regions of the catalyst distributed in an exhaust gas flow direction; and a fuel injection unit that determines for each of the regions whether an increase in fuel injection amount is required on the basis of the corresponding bed temperature acquired by the bed temperature acquisition unit, that calculates an increase in fuel injection amount for each region and that injects fuel of an amount including the sum of the calculated increase values.