Abstract: A shaft/roller unit for tracked vehicles which has a long life and resistance to wear is formed by a shaft (54) which has a shoulder (55) in its central portion, perpendicular to its axis, and onto which two wholly hardened steel half-rollers (56, 57) are fitted, one on each side of the shoulder, with the interposition of antifriction bushings (58, 59), the half-rollers grasping the shoulder (55) and, when they have been welded together along a mating contact and locating surface (60), forming a unitary roller which has a predetermined axial position on the shaft and can withstand considerable axial stresses.