Strapping device including: frame defining supporting area to place thereon a strap being processed, tensioning assembly to lock and tension, on command, at least part of the strap, welding assembly for joining, on command, at least two edges of the strap, a first drive member to actuate at least part of the tensioning and welding assemblies, and second drive mechanism operatively connected to at least the first drive member, at least part of the tensioning assembly and the welding assembly, and including a first element to carry out at least first and second movements, the first element defining an intermediate position relative to the frame starting from which the drive member actuates at least part of the tensioning assembly if the first element carries out the first movement and alternately actuates at least part of the welding assembly if the first element carries out the second movement.