An aesthetically designed indoor unit for an air conditioner. An indoor unit (1) for a ceiling embedded air conditioner has a casing (2) and a flat panel (3). A drawing opening (21a) for drawing indoor air and a discharge opening (21b) are formed in a decorative panel (2b) of the casing (2). The flat panel (3) can take both a closed position for closing the drawing opening (21a) and an open position for opening the drawing opening (21a). When the flat panel (3) takes the open position, at least that first portion (P1) of the flat panel (3) which is away from the discharge opening (21b) is separated from the casing (2).
