Abstract: An automatic apparatus for strapping together a first and a second superposed elongated body (1,2) even in a nonangulated axial relationship, with particular reference to reinforcement for reinforcing concrete, essentially comprising a rotatable system of locking devices (141) capable of engaging respective ends of two wire-like elements, relatively stiff, previously proportioned and shaped, straddling over said first elongated body of under said second elongated body, side by side opposed edges of said second elongated body or said first elongated body, respectively, so that following the rotation around its own axis of said system of locking devices the ends of said wire-like elements are twisted together in pairs under said second elongated body or all together over the first elongated body, in order to perform the sought strapping.