Abstract: An apparatus of the aerosol sampler type with cascade impaction and uniform deposition comprising a conical air inlet fixed to a tight, hollow, cylindrical chamber of revolution constituted by the superimposing of several stages in the form of hollow cylinders of revolution traversed by the air flow from the conical inlet and each having a circular plate perforated with holes located on concentric circles coaxial to the plate and having an identical diameter progressively decreasing in each stage, as well as a collection disk located downstream of the perforated plate and whose diameter is smaller than the internal diameter of the impacter chamber, incorporating a pump for ensuring the vertical downward circulation of the air and driving gears for the relative rotation of each perforated plate with respect to the corresponding collection disk, wherein in each stage the axis of rotation of the disk passes through the disk and is offset relative to the axis of the circular perforated plate.