[Object] To provide a drive device capable of increasing the drive precision of a movable member for generating power and capable of suppressing the generation of abraded particles.[Solving Means] A fluid machine (100) according to this embodiment has a structure in which a connecting rod as a movable member of a pump unit (20) is not connected to a circling shaft (13) of a motor unit (10) via a bearing but fixed to the circling shaft (13). In other words, the connection structure between the circling shaft (13) and the connecting rod is a structure using no bearings, and the integration, that is, the rigidity, of the circling shaft (13) and the connecting rod can be increased, which can increase the drive precision of the connecting rod. Further, since there are no sliding portions between the circling shaft (13) and the connecting rod, the generation of abraded particles can be suppressed and the reliability of the fluid machine (100) can be increased.