An engine system comprising: an engine including a plurality of cylinders (11, 12, 13, 14) generating driving torque by combustion of fuel; a cylinder deactivation apparatus "CDA" disposed at one or more of the plurality of cylinders (11, 12, 13, 14) for selectively deactivating the one or more of the plurality of cylinders (11, 12, 13, 14); a first exhaust manifold connected to cylinders (12, 13) at which the CDA apparatus is disposed; a second exhaust manifold connected to cylinders (11, 14) at which the CDA apparatus is not disposed; a turbocharger including a turbine rotated by exhaust gas exhausted from the first exhaust manifold, and further including a compressor rotated together with the turbine for compressing air supplied to the cylinders (11, 12, 13, 14); and an electric supercharger including a motor and an electric compressor operated by the motor for supplying compressed air to the cylinders (11, 12, 13, 14), wherein the turbine is connected to a first exhaust line connected to the first exhaust manifold, and exhaust gas discharged through a second exhaust line connected to the second exhaust manifold is directly discharged to an exhaust gas purification apparatus; wherein the cylinders (11, 12, 13, 14) are in a four-cylinder engine in which a first cylinder, a second cylinder, a third cylinder, and a fourth cylinder are sequentially disposed, and the CDA apparatus is disposed at the second cylinder and the third cylinder, wherein a first exhaust line connected to the first exhaust manifold and a second exhaust line connected to the second exhaust manifold are joined at a main exhaust line, and an exhaust gas purification apparatus is disposed at the main exhaust line. an engine including a plurality of cylinders (11, 12, 13, 14) generating driving torque by combustion of fuel; a cylinder deactivation apparatus "CDA" disposed at one or more of the plurality of cylinders (11, 12, 13, 14) for selectively deactivating the one or more of the plurality of cylinders (11, 12, 13, 14); a first exhaust manifold connected to cylinders (12, 13) at which the CDA apparatus is disposed; a second exhaust manifold connected to cylinders (11, 14) at which the CDA apparatus is not disposed; a turbocharger including a turbine rotated by exhaust gas exhausted from the first exhaust manifold, and further including a compressor rotated together with the turbine for compressing air supplied to the cylinders (11, 12, 13, 14); and an electric supercharger including a motor and an electric compressor operated by the motor for supplying compressed air to the cylinders (11, 12, 13, 14), wherein the turbine is connected to a first exhaust line connected to the first exhaust manifold, and exhaust gas discharged through a second exhaust line connected to the second exhaust manifold is directly discharged to an exhaust gas purification apparatus; wherein the cylinders (11, 12, 13, 14) are in a four-cylinder engine in which a first cylinder, a second cylinder, a third cylinder, and a fourth cylinder are sequentially disposed, and the CDA apparatus is disposed at the second cylinder and the third cylinder, wherein a first exhaust line connected to the first exhaust manifold and a second exhaust line connected to the second exhaust manifold are joined at a main exhaust line, and an exhaust gas purification apparatus is disposed at the main exhaust line.