To provide a long nut capable of arranging bars simply with high work efficiency in a construction work of a tunnel.

This long nut for constructing a mesh bar is constituted by fixing a binding auxiliary bar on a side face of the long nut 3. Preferably, a length of the long nut 3 is 30 to 100 mm. The long nut 3 is used by screw- fitting it in a tip part of a hanging reinforcing bar attached to an anchor part when, for example, bar arrangement work for constructing a tunnel is done. The binding auxiliary bar 23 facilitates binding and fixing works of a set-up reinforcing bar.