A process for producing paper, board and cardboard in the presence of an aqueous slurry of components comprising finely divided fillers coated at least partly with water-soluble amphoteric copolymers, which involves adding, further to the aqueous slurry of components comprising finely divided fillers, at least one cationic and/or amphoteric polymer comprising as structural element no esters of unsaturated carboxylic acids with quaternized amino alcohols to the fiber suspension prior to sheet forming.