In the case of regeneration control in a manual regeneration mode, second exhaust gas temperature rise control performing post injection in addition to multi-injection is stopped when an intake temperature (Ta) becomes higher than a predetermined third judgment temperature (Tc3) and when the first exhaust gas temperature (Tg1) of exhaust gas flowing into an oxidation catalyst device (12a) is higher than a predetermined judgment temperature (Tc1) and the temperature (Tg2) of exhaust gas flowing into a DPF device (12b) is higher than a predetermined judgment temperature (Tc2), and switching is made to third exhaust gas temperature rise control performing post injection in addition to normal injection. In the case of regeneration control in a manual regeneration mode of the continuous regeneration DPF device (12) of an engine (10), overheat of the engine (10) can be prevented by suppressing temperature rise of engine cooling water without stopping an air conditioner.