A fluid dynamic bearing device, comprising: a bearing member; a shaft member that is inserted along an inner periphery of the bearing member and forms a radial bearing gap with respect to an inner peripheral surface of the bearing member; and a dynamic pressure generating groove region having a plurality of dynamic pressure generating grooves inclined with respect to an axial direction and arrayed in a circumferential direction, the dynamic pressure generating groove region being provided on the inner peripheral surface of the bearing member or an outer peripheral surface of the shaft member, which forms the radial bearing gap, the dynamic pressure generating groove region comprising: a first region for generating a fluid dynamic pressure in the radial bearing gap when the bearing member and the shaft member are rotated relative to each other in a forward direction; a second region for generating a fluid dynamic pressure in the radial bearing gap when the bearing member and the shaft member are rotated relative to each other in a reverse direction; and an annular projecting portion provided to be closer to a counterpart member with respect to a groove bottom of each of the plurality of dynamic pressure generating grooves, the fluid dynamic bearing device being characterized in that the annular projecting portion is provided along an axial end of the dynamic pressure generating groove region corresponding to an end portion on an open-to-air side of the radial bearing gap, whereby the plurality of dynamic pressure generating grooves is located on an axial side of the annular projecting portion opposed to an open-to-air axial side of the annular projection portion. a bearing member; a shaft member that is inserted along an inner periphery of the bearing member and forms a radial bearing gap with respect to an inner peripheral surface of the bearing member; and a dynamic pressure generating groove region having a plurality of dynamic pressure generating grooves inclined with respect to an axial direction and arrayed in a circumferential direction, the dynamic pressure generating groove region being provided on the inner peripheral surface of the bearing member or an outer peripheral surface of the shaft member, which forms the radial bearing gap, the dynamic pressure generating groove region comprising: a first region for generating a fluid dynamic pressure in the radial bearing gap when the bearing member and the shaft member are rotated relative to each other in a forward direction; a second region for generating a fluid dynamic pressure in the radial bearing gap when the bearing member and the shaft member are rotated relative to each other in a reverse direction; and an annular projecting portion provided to be closer to a counterpart member with respect to a groove bottom of each of the plurality of dynamic pressure generating grooves, a first region for generating a fluid dynamic pressure in the radial bearing gap when the bearing member and the shaft member are rotated relative to each other in a forward direction; a second region for generating a fluid dynamic pressure in the radial bearing gap when the bearing member and the shaft member are rotated relative to each other in a reverse direction; and an annular projecting portion provided to be closer to a counterpart member with respect to a groove bottom of each of the plurality of dynamic pressure generating grooves, the fluid dynamic bearing device being characterized in that the annular projecting portion is provided along an axial end of the dynamic pressure generating groove region corresponding to an end portion on an open-to-air side of the radial bearing gap, whereby the plurality of dynamic pressure generating grooves is located on an axial side of the annular projecting portion opposed to an open-to-air axial side of the annular projection portion.