The present invention relates to a method for treating the surface of a banknote (1) comprising, on at least one of its opposing surfaces (20, 21), at least a printed item comprised of at least a design (3), this surface (20, 21) and its associated printed item (3) being covered in a transparent protective coating (R), characterized by the fact that a coating is applied via printing, said coating containing a varnish and an organic chemical compound incorporating fluorine atoms in the form of at least a perfluoro-polyether (PFPE) group, on said surface (20, 21), and by the fact that it is dried.