Abstract: A system for cooling an internal combustion engine having a turbocharger includes an engine coolant recirculating circuit and a turbocharger coolant recirculating circuit. Coolant is fed from the former recirculating circuit to the latter recirculating circuit. The turbocharger coolant recirculating circuit includes a coolant feeding tank at a higher position than those of the turbocharger and a radiator. Coolant is recirculated from a water jacket for the engine via a coolant intake pipe, a water jacket for the turbocharger, a coolant discharge pipe, the coolnt feeding tank, a coolant return pipe and the pump. Air in the both recirculating circuits is collected in an air venting portion of the radiator and then transferred to an air chamber in the feeding tank via an one-way valve.