A temperature control device for a catalyst, which is capable of rapidly activating a catalyst while maintaining reduced exhaust emissions, by properly controlling the temperature of exhaust gases according to an activated state of the catalyst. If the catalyst is determined not to be in the activated state, based on an acquired temperature of the catalyst, the temperature control device for a catalyst sets a temperature higher than the temperature of the catalyst by a predetermined temperature is set as a target exhaust gas temperature. Further, the temperature control device controls a combustion control parameter including at least one of an amount of recirculation of exhaust gases by an EGR device, an amount of intake air drawn into an engine, a supply amount and a supply timing of fuel supplied into the engine, according to the set target exhaust gas temperature.