A device for inserting an articulation pin (28) to pivotally connect the outer plates (12) and the inner plates (14) of a chain, particularly a bicycle chain. The device comprises an articulation pin (28) and a guide element (30) which is to be separated from the pin (28) after the insertion of the pin (28) within aligned holes (16, 18) of the plates (12, 14). The pin (28) is provided at one end thereof with a snap engaging portion (38) shaped so as to expand the holes (16) of the outer plates (12) in a radial direction during the insertion of the pin.