A drying tunnel applicable to products of fruits and vegetables for drying, using ambient temperature dry air. The tunnel has an outer casing fitted with two independent stories which has openings at the ends of the upper floor, which crossed inside in an upward direction by a conveyor belt which is in turn crossed in a counterflow direction by a particular flow of drying air at ambient temperature. Humidity of the products is absorbed by traveling along the conveyor belt which passes through the upper flow. The upper floor is blown by fans treated by air passing through a refrigeration evaporator, condenser, and compressor located on the upper floor. Air curtains are at the tunnel openings to minimize escaping air. Air filters are included to eliminate suspended particles from the product surface.