To provide an indoor unit body of an air conditioner capable of improving collection of dust and the like removed by a fan cleaning device, and keeping the inside in a clean state for a long period.

An air filter 11 and a heat exchanger 8 are disposed in an air distribution passage 24 communicating a suction opening 4 and a supply opening 6 in an indoor unit body 1, a fan 21 of the indoor blower 20 is disposed in a casing 23 forming a ventilation secondary side of the heat exchanger, an air filter cleaning device A, an inside cleaning device F composed of the fan cleaning device B for cleaning a fan, and an air discharge device D for discharging dust and the like generated in accompany with the action of the devices outdoors are disposed in the indoor unit body, and an air filter cleaning operation, an inside drying operation, an ozone sterilizing operation and a fan cleaning operation are successively executed in an inside cleaning operation.