A bearing device has rolling bearings each having an inner ring mounted on a main shaft and an outer ring; an inner ring spacer interposed between the inner rings of the neighboring rolling bearings and mounted on the main shaft; an outer ring spacer interposed between the outer rings of the neighboring rolling bearings; and a cooling structure. The cooling structure includes a nozzle provided in the outer ring spacer to supply a cooling fluid to the rolling bearings by blowing the cooling fluid to an outer peripheral surface of the inner ring spacer. The nozzle has a discharge port side that is inclined forwardly with respect to a direction of rotation of the main shaft. The outer peripheral surface of the inner ring spacer is shaped to guide the cooling fluid, discharged from the nozzle, towards the neighboring rolling bearings on both sides.