The invention relates to an exhaust gas aftertreatment system for an internal combustion engine, in particular for a gasoline engine that is spark-ignited by means of spark plugs. A first three-way catalytic converter is situated in an exhaust gas system that is connected to an outlet of the internal combustion engine in a position close to the engine. Downstream from the first three-way catalytic converter, a four-way catalytic converter or a combination of a particle filter and a second three-way catalytic converter downstream from the particle filter is situated in the underbody position of the motor vehicle. An exhaust gas burner with which hot exhaust gas is introducible into the exhaust gas system downstream from the first three-way catalytic converter and upstream from the four-way catalytic converter or the particle filter is provided at an exhaust duct of the exhaust gas system. The exhaust gas burner is supplied with fresh air by a secondary air pump. The invention further relates to a method for exhaust aftertreatment of an internal combustion engine having such an exhaust gas aftertreatment system.