A tapered roller bearing includes: an inner ring; an outer ring provided on an outer peripheral surface of the inner ring via an annular space so as to be disposed on the same center line as the inner ring; a plurality of tapered rollers rollably disposed in the annular space; and a cage retaining the plurality of tapered rollers. The tapered roller bearing is configured such that: liquid lubricant flows through the annular space; and among the inner ring, the outer ring, the tapered rollers, and the cage, at least one rotating component configured to rotate at the time of bearing rotation is provided with a vaporization promotion mechanism configured to decrease a pressure of the lubricant at the time of bearing rotation so that the pressure of the lubricant reaches a saturation vapor pressure at which the lubricant changes from a liquid phase to a vapor phase.