To provide a coupling nail whose resistance to extracting force does not deteriorate and whose end is hard to crack and whose smooth driving operation is possible.

There is provided a set of coupled nails 1 employed for making a nailing double charging magazine 16 which can load, to form double lines of the coupled nails, two sets of the coupled nails 1 made by coupling upper and lower portions of a plurality of nails by using coupling belts 3. The coupling belt 3 is made of synthetic resin and surrounds each nail. One lateral side 3a of the coupling belt 3 is formed flat and the flat lateral side 3a is provided adjacently to a nail head 2b. In addition, in the magazine, a first-raw coupled nails 1A and a second-raw coupled nails 1B are loaded so that nail heads 2b of one coupled nail abut on the flat lateral side 3a of the upper coupling belt 3A of the other coupled nails.