This air pump device is provided with: an electric pump unit including a pump mechanism and a motor; a case; and a vibration-proof member. The pump mechanism and the motor are arranged side by side in the axial direction of the motor. The pump mechanism has an inlet and an outlet at an end in the axial direction on the opposite side of the motor. The case has a first wall and a second wall which are located on opposite sides in the axial direction of the motor and which face the electric pump unit. The vibration-proof member is provided with: a first axial vibration-proof unit interposed between the electric pump unit and the first wall; and a second axial vibration-proof unit interposed between the electric pump unit and the second wall. The first axial vibration-proof unit covers the inlet.