A barrel balancing device for collapsible firearms (20) wherein at least one barrel (9) which is rotatable about a fixed hinging point (7) arranged on a action body (6), wherein an open-close top lever (13) is provided between a closed aligned position of the at least one barrel (9) and the action body (6), and a position disengaged and rotated upon opening of said at least one barrel (9) with respect to said action body (6), the at least one barrel (9) being carried by an iron fore-end (8), wherein at least one elastic or viscoelastic group (21, 22, 23, 24, 25, 26) is foreseen which interacts between the iron fore-end and the action body to oppose the falling motion of the at least one barrel (9), once the open-close top lever (13) is unlocked, and to realize a balancing push with respect to the weight of the at least one barrel (9) when the collapsible firearm (20) is closed.
