The invention relates to an exhaust system for internal combustion engines, especially for use in motor vehicles, comprising an exhaust gas purifying device and a temperature control device disposed in the exhaust path between the internal combustion engine and the exhaust gas purifying device, said temperature control device being provided with a heat exchanger. In order to simplify the construction of such an exhaust system and to achieve a defined cooling capacity, the heat exchanger is configured as a radiation cooler with internal radiation sheets radiating the energy towards the housing.