An air filter group for air supply to internal combustion engines of motor vehicles, of a type comprising an external casing provided with an inlet opening of the air to be filtered, and an outlet opening of the filtered air, and a removable cover, the inlet and outlet openings being separated by a removable filter cartridge which comprises a hollow cylindrical filter wall crossed by the air in a centripetal direction, in which the at least a filter cartridge is fixed to the cover in which cover a chamber is present, delimited by a base provided with at least a hole at which the at least a cartridge is fixed, by an opposite wall to the base and by an annular wall located between the base and the opposite wall and comprising the outlet hole of the filtered air, the cover being destined to be inserted sealedly in the casing.