To provide a low-cost hydrodynamic fluid bearing apparatus which has a low friction loss and wear at the time of starting/stopping, and a high stability.

A hydrodynamic fluid bearing apparatus, which comprises: a sleeve 2; a shaft 1 which rotates relatively with respect to the sleeve 2; and a lubrication fluid 5 filling a gap between the shaft 1 and the sleeve 2, characterized in that in either the inner peripheral surface 2a of the sleeve 2 or the outer peripheral surface of the shaft 1, a herringbone dynamic pressure groove constituted by a groove portion 10 great in gap with respect to facing periphery and a hill portion 12 having a small gap with respect to the facing periphery is formed, and in that the groove portion 10 is formed in 45°≤β≤75° of slope angle β with respect to rotational axis direction.

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