The present invention relates to a catalyst system for treating Diesel exhaust gas, which comprises in the direction of flow of the exhaust gas - a nitrogen oxide storage catalyst containing a nitrogen oxide storage component and precious metal, - and-a Diesel particulate filter which contains precious metal selected from the series of platinum, palladium and platinum and palladium, characterized in that the precious metal load of the nitrogen oxide storage catalyst is 100 to 180 g/ft3 (3.53 to 6.36 g/l) and the precious metal load of the Diesel particulate filter is 5 to 35 g/ft3 (0.18 to 1.24 g/l).