A dial device includes a body, a first dial knob supported to the body so as to rotate around a predetermined axis, a second dial knob supported to the body so as to rotate around the predetermined axis, and the second dial knob being provided so as to surround the first dial knob, a gear which rotates in response to a rotation of the second dial knob, and is provided on the body, and a pulley unit which includes a first pulley having a connection portion and a second pulley having a gear portion, the second pulley being arranged coaxially with the first pulley. The connection portion of the first pulley is connected to the first dial knob and the gear portion of the second pulley is meshed with the gear in a state that the pulley unit is attached to the body.