An endoscope system 1 includes: an actuator 20 having an SMA wire 21 and driving a moving member 30 for moving a lens 24 an output control circuit 52 a detection circuit 53 and a CPU 51. The CPU 51 outputs a driving signal to the output control circuit 52, on a basis of an instruction to move the lens 24, and on the basis of a position of the moving member 30 corresponding to a resistance value detected by the detection circuit 53. In response to a moving instruction to move the lens 24 from a far-point position to a near-point position, the CPU 51 outputs the driving signal so that a current for moving the moving member 30 from the far-point position to a position beyond the near-point position is passed through the SMA wire 21 to heat the SMA wire. The CPU 51 then performs preheating control, holding constant current transition control, and reheating control.
