An electrically controlled mechanical watch (1) includes a mainspring (40), a wheel train (50), a hand that displays the time (60), a speed regulator (70) that controls a rotation cycle of the wheel train, a control unit (10) that controls the speed regulator (70), a power generator (70) that converts mechanical energy of the mainspring to electrical energy, a first power accumulation device (31) that accumulates the electrical energy of the power generator (70) and supplies the electrical energy to the control unit (10), a second power accumulation device (32) that is coupled to the first power accumulation device in parallel via a switch (33) and that accumulates the electrical energy, and a detection unit (13) that detects a mechanical energy amount accumulated in the mainspring. In a case in which the switch (33) is in an off state, when it is detected that the mechanical energy amount exceeds a first set value, the control unit controls (10) the switch (33) from the off state to an on state. In a case in which the switch (33) is in the on state, when it is detected that the mechanical energy amount falls below a second set value, the control unit (10) controls the switch (33) from the on state to the off state.