A power supply control method of a production system including a first unit and a second unit includes: starting power supply for operation of the second unit in accordance with a signal acquired according to an operation status of the first unit (S41); starting the operation by the second unit after the start of the power supply (S44); acquiring stop time information indicating time from when the operation ends to when a next operation of the second unit starts (S22); determining, based on the acquired stop time information, whether or not to stop the power supply after the started operation ends (S24); and stopping the power supply when it is determined to stop the power supply (S48).