A device for coating seeds with a liquid dressing solution, including a housing delimiting a chamber for accommodating the seeds, a rotating system for mixing the seeds and the dressing solution, an air duct for feeding hot air into the chamber and a separating unit which is permeable to the hot air and separates the air duct from the chamber. According to this invention, the separating unit includes at least one perforated metal sheet that has an inner face facing towards the chamber, an outer face facing towards the air duct and a plurality of projections, wherein a projection rises obliquely in the direction of the outer face and forms an opening inlet, which is inclined to the metal sheet plane, on the outer face. This invention further relates to a method in which the device is used.