A clutch-by-wire system includes: an automatic clutch having a clutch disposed on a power transmission system pathway, and a clutch actuator; a clutch pedal sensor; and an electronic control device which automatically controls an operation of the clutch actuator in response to an operating state at the time of an automatic mode and controls an operation of the clutch actuator on the basis of a signal from the clutch pedal sensor at the time of a manual mode, wherein the electronic control device compares a first control amount manually controlled in response to a signal from the clutch pedal sensor with a second control amount automatically controlled in response to the operating state and controls the clutch actuator in accordance with the control amount on a non-engagement side out of the first control amount and the second control amount.