The invention discloses a cleaning control method for an evaporator of an air conditioner. The method comprises following steps: A, controlling a compressor to open and enter a heating mode when the evaporator is cleaned; B, controlling a three-way valve to communicate with a water adding pipe, and starting a water-adding pump, putting water of the water-adding pump to the evaporator through the water adding pipe and heating the water for cleaning the evaporator; C, controlling water to flow into a water tank cyclic-cleaning evaporator, wherein water flows from the evaporator and is collected by a water-containing plate; D, controlling the three-way valve to communicate with a water drainage pipe after the cyclic-cleaning satisfies the pre-set condition and draining water in the water-containing plate out of the air conditioner. The invention further discloses a cleaning control device for the evaporator of the air conditioner and the air conditioner. The cleaning control method, device for the evaporator of the air conditioner and the air conditioner have following beneficial effects: hot water is utilized for cleaning the evaporator; while cleaning effect is ensured, resources can be saved; through the three-way valve, water is switched between the water evaporator and the outside of the air conditioner; components and parts are saved; and cost is reduced.