To provide a user-friendly water heater remote controller.

The water heater remote controller can bidirectionally communicate with a water heater and includes: switch parts 3f and 3h for receiving user's operation; switch display parts 3g and 3i comprised of electronic paper for displaying information on the switch parts 3f and 3h, which are provided with the switch parts 3f and 3h; and a control part for rewriting display contents of the electronic paper comprising the switch display parts 3g and 3i according to the water heater state or a state relating to the water heater.