The invention discloses an air conditioner with a hidden air supply outlet. The air conditioner comprises a shell, a front panel, an inner plate and an air supply outlet cover plate, wherein the front side of the shell is open; the shell is provided with a return air inlet; the front side of the shell is enclosed by the front panel; the front panel is provided with an air supply outlet; the inner plate is arranged on the back side of the front panel in a matching way so as to support the front panel; an accommodating cavity which is communicated with the air supply outlet is defined between the inner plate and the front panel; the inner plate is provided with an opening which corresponds to the air supply outlet; the air supply outlet cover plate is movably arranged in the accommodating cavity, and moves between an air supply outlet position where the air supply outlet is closed and an accommodating cavity position where the air supply outlet is opened. According to the air conditioner disclosed by the invention, the air supply outlet over plate capable of moving in the accommodating cavity is adopted, so that the aims of opening the air supply outlet during working of the air conditioner and hiding the air supply outlet during shutdown of the air conditioner can be fulfilled, and the air conditioner is attractive in appearance; meanwhile, dust can be prevented from falling into the air supply outlet when the air conditioner does not work; moreover, the air conditioner has the advantages of simple structure, easiness in assembling and low cost.