Turbo machinery includes a rotating body, a stator, and a labyrinth seal disposed in a gap between the rotating body and the stator. The labyrinth seal includes a first seal fin and a second seal fin both of which protrude from a portion of one of the rotating body and the stator toward an opposing portion of the other one of the rotating body and the stator. The first seal fin is disposed on the high-pressure side of the center of the labyrinth seal in the axial direction of the rotating body. The second seal fin is disposed on the low-pressure side of the first seal fin to form a cavity together with the first seal fin. A gap to the portion opposing the first seal fin is smaller than a gap to the portion opposing the second seal fin.
