Abstract: A workpiece abutment structure for a milling machine to carry out accurate positioning of the workpiece during the machining includes a body element to be supported to a bench of the milling machine and a number of support elements shaped as a rectangular parallelepiped and mountable in a superposed configuration to one another into a support post of a desired height. Further, the structure includes a number of straight abutment bars and corresponding support holes and lockings in the support elements to push the abutment bar through the support element and lock it in a desired position. In addition, the abutment structure has a locking bar, and the support elements have a corresponding hole to lock the support elements to one another into a support post of a desired height.