SECONDARY AIR INJECTION SYSTEM

A secondary air injection system may include an engine that includes a plurality of cylinders that generate a driving torque of a vehicle by combustion of a fuel; a main line connected to an exhaust manifold or an exhaust line which is connected to the plurality of cylinders; a recirculation line which is branched from the main line and then connected to an intake manifold; an air injection line which is branched from the main line and then connected to an intake line; and an electric supercharger which is provided in the intake line.