A turbo machine includes a rotation shaft that comprises a first taper portion and a first cylinder portion, the first taper portion decreasing in diameter toward one end of the rotation shaft, the first cylinder portion being constant in diameter in an axial direction of the rotation shaft; a first impeller that is fixed to the rotation shaft and that is used for compressing or expanding working fluid; a first bearing that rotatably supports the first taper portion and the first cylinder portion; and a second bearing that is positioned on an opposite side of the first impeller from the first bearing in the axial direction of the rotation shaft and that supports the rotation shaft both in the axial direction and a radial direction of the rotation shaft.