PROBLEM TO BE SOLVED: To provide an injection device that can efficiently release the adhesion of a stator and a rotor of an ultrasonic motor.SOLUTION: An injection device according to the present invention is an injection device 1 for injecting a drug solution, and comprises: an ultrasonic motor part 3 that includes an ultrasonic motor 31 a drive mechanism 4 that is driven by the ultrasonic motor part 3 so as to send the drug solution when the ultrasonic motor 31 is normally rotated and a control device 5 that controls the ultrasonic motor 31 of the ultrasonic motor part 3. The ultrasonic motor 31 includes a stator 32 and a rotor 33. The control device 5 exercises control so that the ultrasonic motor 31 alternately repeats normal rotation and reverse rotation in order to release the adhesion of the stator 32 and the rotor 33.SELECTED DRAWING: Figure 5
