To provide a scaffold beam member for which a lock mechanism in a simple structure without difficulty in mounting work or detaching work is provided together with a wedge part.

For the scaffold beam member, hooks 13 are provided on both ends of a pipe material and the hook 13 is driven from above to a binding holder formed on a column and communicated in the vertical direction to be supported. In the scaffold beam member, stoppers 23 and 24 of a lock metal fitting 21 are fitted between bearing holes 18 formed near the lower end of the sidewall 15 of the hook 13 and are energized to be exposed outwards by a torsion spring 22. In the case that the stoppers 23 and 24 are at a first turning position, since a second engaging surface 28 is moved in the direction that the stoppers 23 and 24 mutually approach, the hook 13 can be driven. Once the hook 13 is driven, a first engaging surface 27 is engaged and the hook 13 cannot be pulled out upwards. In the case of pulling out the hook 13, the stoppers 23 and 24 are turned to a second turning position and a third engaging surface 29 is turned upwards.