To provide a tread for which detaching work can be efficiently performed.

A tread 1 includes: a tread body 10 which is a rectangular plate having long side parts 11 and short side parts 12; hooks 30 provided on both ends in a width direction of the two short side parts 12 respectively, to be engaged from an upper part with a horizontal member 2 constructing a scaffold; and two lock pieces 21 two each of which are arranged separate from each other at the two short side parts 12, to be projected and engaged with a lower side of the horizontal member 2 to prevent falling to an upper part of the tread body 10. The two lock pieces 21 arranged at the same short side part 12 are connected by a connecting piece 23 which links movements.