An apparatus for improving the characteristics of wetting water in offset printing comprises, in an operatively and functionally intercoupled relationship, a device for supplying the wetting water, a device for filtering the supplied wetting water, designed to provide an actively filtered wetting water, a plurality of magnets adapted to subject the filtered wetting water to a continuous and strong magnetic processing, a pH controlling device, adapted to control the wetting water pH at a preset acid pH value, and a device adapted to control the wetting water electrical conductivity at a set conductivity value.