In an air conditioner, reverse inhalation is prevented while broad band noise and wind sound are reduced. There are provided a projection 12b arranged at the leading end of a stabilizer 12 on the downstream side of an air stream F flowing along a surface 12a of the stabilizer opposing an impeller so as to protrude toward the impeller to define the shortest distance to the impeller, and a plurality of grooves 12e or projections provided on the opposing surface on the upstream side of the projection 12b so as to disturb the air stream flowing along the opposing surface 12a. The positions of the grooves 12e or the projections are arranged apart in a rotational axis direction E. A plurality of convex portions are provided so as to disturb an air stream flowing along a surface of a casing opposing the impeller, and the positions of the convex portions are arranged apart in the rotational axis direction of the impeller.
