A twin-scroll turbocharger configured to be driven by exhaust gas of an engine, comprising: a turbine housing of a turbocharger, two exhaust gas introducing passages comprising a front scroll and a rear scroll, each of which is formed in the turbine housing along an axis line of a rotatable shaft of the turbocharger, a separation wall configured to separate the rear scroll and the front scroll, and a rotor blade mounted to the rotatable shaft and configured to rotate the rotatable shaft by exhaust gas, wherein the rear scroll is disposed so that a center line (CLr) on a cross-sectional surface along a radial direction is substantially perpendicular to the axis line, the front scroll is disposed so that a center line (CLf) on a cross-sectional surface along a radial direction has a gradient toward a side of an outlet of the rotor blade with respect to the axis line, characterized in that an extended line of an inclined surface of the front scroll on a side of the turbine housing and an inlet of the rotor blade intersect at a position in a central portion of the inlet of the rotor blade, and the front scroll has an outlet portion formed so that a crossing portion at which an extended line of an inner periphery surface of the turbine housing, having a gap (α) of a constant width between the inner periphery surface and an outer circumferential portion of the rotor blade, and the extended line of the inclined surface intersect is at a position within a width of the inlet of the rotor blade and outer along the radial direction than the inlet of the rotor blade, and wherein a connecting portion, where the inner periphery surface of the turbine housing and the inclined surface are connected, is formed in an arc-like shape, and the center of the arc-like shape is, in the radial direction, on the same position as the inlet of the rotor blade or on a position farther than the inlet of the rotor blade from the axis line of the rotatable shaft. a turbine housing of a turbocharger, two exhaust gas introducing passages comprising a front scroll and a rear scroll, each of which is formed in the turbine housing along an axis line of a rotatable shaft of the turbocharger, a separation wall configured to separate the rear scroll and the front scroll, and a rotor blade mounted to the rotatable shaft and configured to rotate the rotatable shaft by exhaust gas, wherein the rear scroll is disposed so that a center line (CLr) on a cross-sectional surface along a radial direction is substantially perpendicular to the axis line, the front scroll is disposed so that a center line (CLf) on a cross-sectional surface along a radial direction has a gradient toward a side of an outlet of the rotor blade with respect to the axis line, an extended line of an inclined surface of the front scroll on a side of the turbine housing and an inlet of the rotor blade intersect at a position in a central portion of the inlet of the rotor blade, and the front scroll has an outlet portion formed so that a crossing portion at which an extended line of an inner periphery surface of the turbine housing, having a gap (α) of a constant width between the inner periphery surface and an outer circumferential portion of the rotor blade, and the extended line of the inclined surface intersect is at a position within a width of the inlet of the rotor blade and outer along the radial direction than the inlet of the rotor blade, and wherein a connecting portion, where the inner periphery surface of the turbine housing and the inclined surface are connected, is formed in an arc-like shape, and the center of the arc-like shape is, in the radial direction, on the same position as the inlet of the rotor blade or on a position farther than the inlet of the rotor blade from the axis line of the rotatable shaft.