A manipulator device for a milling tool for prosthetic surgery operations, comprising a central body and at least attachment members angularly constrained to the central body to achieve the selective attachment/detachment of the central body to/from the milling tool. The attachment members are provided at one end of the central body and comprise mechanical attachment elements comprising an insertion seating, blind and open toward an insertion end in a direction axial to a median axis of rotation of the central body and at least a groove made radially through to the insertion seating and open toward the insertion end. The attachment members also comprise magnetic attachment elements comprising a magnetic element provided inside the insertion seating, in order to magnetically hold a connection element of the tool inside the insertion seating.