A boring head system for boring machines includes couplings or drive units for the rotation-translation of at least one boring rod and of at least one covering tube that are coaxial and hollow, such to allow the passage of pressurized water/air as well as the upward flow of waste fluid consisting of water/air mixed with debris along the interspace defined between the rod and the covering tube, and also includes a protection screen or wall completely enveloping the rod and the covering tube, suited to be positioned near or at the level of an upper annular opening of the interspace, out of which the waste fluid flows, in such as way as to intercept the waste fluid in all directions and to convey it downwards.