Provided is a suction device that can suppress sound and vibration during use. A suction device includes a flow-passage forming section (1) having a suction port (20) from which fluid is sucked, a discharge port (29) from which the fluid is discharged, and a flow passage (2) which is sealed from an outside except at the suction port (20) and the discharge port (29) and through which the fluid flows, and a piezoelectric driving part (33) that generates a flow of the fluid in the flow passage (2). The piezoelectric driving part (33) includes a diaphragm (37) and a piezoelectric element (34) as a moving part that transmits driving force to the fluid. The moving part is entirely disposed inside the flow passage (2).