An optical terminal device includes: a relay processing circuitry relaying communication between first base stations, respectively connected to optical terminating devices at branch destinations of a transmission path, and a control device controlling the first base stations in accordance with information acquired from a second base station covering a cell overlapping cells of the first base stations; a detecting circuitry detecting a sleep control instruction, issued for one of the first base stations from the control device, from the communication being relayed by the relay processing circuitry; and a control circuitry performing control, via the transmission path, to cause the optical terminating device connected to the one of the first base stations to shift to an operating state or a sleep state, which consumes less power than the operating state, in response to detection of the sleep control instruction, the optical terminating device being one of the optical terminating devices.