Provided is a fluid dynamic bearing device in which an assembly of a bearing sleeve to a housing is facilitated and which has excellent moment rigidity. A fluid dynamic bearing device (1) includes radial bearing parts (R1 and R2) and thrust bearing parts (T1 and T2). Thrust bearing surfaces (C and D) are respectively provided to first and second step surfaces (2d and 2e) of a housing (2), and the thrust bearing parts (T1 and T2) are respectively formed between the thrust bearing surfaces (C and D) and end surfaces (6b and 7b) of seal members (6 and 7) provided while protruding to an outer diameter side of a shaft member (5).