A turbine blade includes: a platform; an airfoil portion extending from the platform in a blade height direction and having a pressure surface and a suction surface extending between a leading edge and a trailing edge; a blade root portion positioned opposite to the airfoil portion across the platform in the blade height direction and having a bearing surface; and a shank positioned between the platform and the blade root portion. The shank has a cross-section which is perpendicular to the blade height direction of the airfoil portion, and in which a line segment connecting a widthwise center position of a leading-edge-side end portion of the shank and a widthwise center position of a trailing-edge-side end portion of the shank is sloped to a center line between a pressure-surface-side contour of the blade root portion and a suction-surface-side contour of the blade root portion.