A steam turbine includes a guide member that is disposed between a first rotor blade row and a second stator vane row to guide a fluid from the first rotor blade row toward the second stator vane row. When seen in a circumferential direction, an outer peripheral surface of an inner ring of the second stator vane row is disposed farther to an inner side in a radial direction than an outer peripheral surface of a platform of the first rotor blade row. The guide member has a guide surface that extends from an outer peripheral surface of a shroud of the first rotor blade row toward an inner peripheral surface of an outer ring of the second stator vane row so as to be inclined toward the inner side in the radial direction as the guide surface approaches a second side from a first side in an axial direction.