Driving system for rotary tools, in tool holder turrets for lathes, machining centres and the like, of the type comprising a stationary base body (2) with a cavity (3) which extends around a longitudinal axis (X-X), a tool holder table (5) which is rotatable with respect to the stationary base body (2) about a rotatiional axis coaxial and coinciding with the longitudinal axis (X-X) of said cavity (3), a plurality of tool housings (7) formed on said table (5) and distibuted along a circumferential zone of the table, each of said housings (7) being equipped with a respective spindle (8) for holding a rotary tool (9) comprising a motion receiving shaft (10a) arranged parallel to said rotational axis (X-X) of the table, a drive shaft (13) for the rotatio of the tools rotatably mounted on said stationary base body (2) with its rotational axis also parallel to said rotational axis (X-X) of the table, motor members (6) for angulary displacing the table (5) about said rotational axis (X-X) to take the motion receiving shaft (10a) of one of any of said tool holder spindles (8) in axial alignment with said drive shaft (13), means (12) capable of being displaced upon command, housed on said stationary body (2), for coupling and decoupling said drive shaft (13) with the motion receiving shaft (10a) of the tool holder spindle which, following the rotation of the table, is aligned with it, driving means (20, 21), mounted on said stationary base body (2) to make said drive shaft (13) for rotating the tools rotate.