Seal segment and rotating machine

A seal segment comprising:

• a seal body having a plurality of thin-plate seal pieces that extend while being inclined forward in a rotational direction of a rotating shaft as the pieces draw farther inward in a radial direction of the rotating shaft, and that are layered in a circumferential direction of the rotating shaft;
• a pair of side plates extending in the circumferential direction so as to cover the seal body from both sides with respect to an axial direction of the rotating shaft;
• and
• a housing having a housing main body that accommodates the seal body while allowing the seal body to protrude inward in the radial direction, and an extending part that is provided to an end portion of the housing main body in the circumferential direction, and that extends inward in the radial direction along an end surface of the seal body in the circumferential direction,
• wherein the extending part extends by being inclined relative to the radial direction more than the end surface of the seal body in the circumferential direction at a time of applying a pre-load.