Abstract: A centrifugal fan (10) with improved efficiency and decreased noise, comprising a fan housing (12), in the form of a fan housing, with parallel sides (22, 23), which are fixed to opposite edges of a casing scroll (24), and a fan or impeller (25) with blades (27), positioned inside the fan housing (12), in such as way that it does or does not overlap the end of a inlet cone (26); a flow sharing device element (20), shaped and produced in a single piece (20) or in more than one piece (28, 30), with at least one appendage facing the inlet cone (26), and if necessary overlapping the impeller (25) and extending for the width of the discharge opening (21), in such as way to allow homogenization of the flow delivered and reduction of vortices, which cause high noise and loss of efficiency of the centrifugal fan (10).