The invention discloses a water heater display control method. A water heater comprises n temperature sensors sequentially arranged in a water tank from the top down, light-emitting modules corresponding to the temperature sensors one to one, and control units electrically connected with the temperature sensors and the light-emitting modules respectively; the control units, according to temperature values detected by the temperature sensors, control on/off of the light-emitting modules corresponding to the temperature sensors; and n is an integer greater than or equal to 2. According to the water heater display control method, one temperature sensor is provided with one light-emitting module correspondingly, and the control units, according to the temperature values detected by the temperature sensors, control on/off of the light-emitting modules corresponding to the temperature sensors, so that people can observe a water level of current heated water more visually, and great convenience is brought to people for use. Furthermore, compared with a technology adopting a display screen in the prior art, the product cost can be reduced greatly by adopting the light-emitting modules.