A turbine of a jet engine, the turbine comprising: a turbine case of a cylindrical shape; turbine blades rotatable about an axis of the turbine case; a turbine nozzle including a plurality of turbine nozzle segments; and a shroud including a plurality of shroud segments annularly placed along an inner peripheral surface of the turbine case while surrounding the turbine blades, wherein each of the turbine nozzle segments of the turbine nozzle is provided with an outer band which includes a front rim extending in a centrifugal direction thereof to a front side of the jet engine, and a rear rim extending in the centrifugal direction thereof; the outer band is adapted to be fixed between the turbine case and the shroud segment by allowing a tip end portion of the front rim to engage with a receiving groove formed in the turbine case, and allowing a band engaging portion formed on an end portion of the shroud segment on the front side of the jet engine to engage with a tip end portion of the rear rim from the rear side of the jet engine; each of the shroud segments of the shroud is provided with a first engaging portion and a second engaging portion, and the shroud segment of the shroud is fixed to the turbine case by allowing the first engaging portion to engage with the turbine case in an axial direction of the turbine case, and allowing the second engaging portion to engage with the turbine case in a radial direction of the turbine case, characterized in that the shroud segment of the shroud is provided with a back plate extending in a centripetal direction from the second engaging portion to a rear side of the jet engine and a tip portion of the back plate is provided with a pressure receiving portion, and the pressure receiving portion is configured to be able to receive a force in the centripetal direction. a turbine case of a cylindrical shape; turbine blades rotatable about an axis of the turbine case; a turbine nozzle including a plurality of turbine nozzle segments; and a shroud including a plurality of shroud segments annularly placed along an inner peripheral surface of the turbine case while surrounding the turbine blades, wherein each of the turbine nozzle segments of the turbine nozzle is provided with an outer band which includes a front rim extending in a centrifugal direction thereof to a front side of the jet engine, and a rear rim extending in the centrifugal direction thereof; the outer band is adapted to be fixed between the turbine case and the shroud segment by allowing a tip end portion of the front rim to engage with a receiving groove formed in the turbine case, and allowing a band engaging portion formed on an end portion of the shroud segment on the front side of the jet engine to engage with a tip end portion of the rear rim from the rear side of the jet engine; each of the shroud segments of the shroud is provided with a first engaging portion and a second engaging portion, and the shroud segment of the shroud is fixed to the turbine case by allowing the first engaging portion to engage with the turbine case in an axial direction of the turbine case, and allowing the second engaging portion to engage with the turbine case in a radial direction of the turbine case, characterized in that the shroud segment of the shroud is provided with a back plate extending in a centripetal direction from the second engaging portion to a rear side of the jet engine and a tip portion of the back plate is provided with a pressure receiving portion, and the pressure receiving portion is configured to be able to receive a force in the centripetal direction.