Indoor unit of air conditioner

The invention provides an air conditioner indoor unit which comprises a shell, an air outlet extending in the length direction of the shell is formed in the shell, and the air outlet comprises an air supply section located on the downstream of an air supply duct and a shielding section located at one end of the air supply section and shielded by internal components of the air conditioner indoor unit; the air guide plate is rotatably arranged at the air outlet, and a containing part is arranged on the side face of the air guide plate; the drainage component is arranged in the containing part, has a first state of protruding out of the side face of the air guide plate and a second state of being contained in the containing part, and is used for guiding the outlet air flow to flow through the part, corresponding to the shielding section, of the air guide plate in the first state; the driving mechanism is arranged on the air guide plate and used for driving the drainage component to be in the first state or the s