Abstract: A machine for folding drawings or documents, comprising hinged blade-holder arms with opposed blades which can be moved back and forth to alternately form the folds of a drawing inserted between them against folding and stop surfaces which work with fold-forming and fold-holding presser components. The improvement comprises the folding and stop surfaces are formed by two half-platens (17, 20) mounted to pivot about pins (18, 19) parallel to the hinge pins (2, 36) of the blade-holder arms (11, 27) and fixed to levers (5, 34). The levers are acted on by cams (3, 37) fixed to the arms (11, 27) hinge pins (2, 36) and designed so that one half-platen presses the drawing or any fold formed at its position against the corresponding presser components (14 or 23) while the other remains free to swing on insertion of the blade (12 or 25) and the corresponding drawing fold to be formed between it and the corresponding presser components.