The invention relates to the technical field of truss robot equipment, in particular to a truss robot maintenance Z-axis anti-falling device. The truss robot maintenance Z-axis anti-falling device comprises vertical beams arranged on a supporting plate, bases, limiting pins and connecting blocks; and the bases are fixed to the supporting plate and provided with sliding grooves matched with the connecting blocks, the connecting blocks are slidably arranged in the sliding grooves, the connecting blocks are provided with first limiting holes matched with the limiting pins, the bases are providedwith second limiting holes, and one ends of the limiting pins penetrate through the first limiting holes to be arranged in the second limiting holes. When the truss robot maintenance Z-axis anti-falling device, the bases are fixed to the supporting plate, meanwhile, first limiting mechanisms limit displacement of the limiting pins on the bases, thus the connecting blocks are limited on the bases,and meanwhile, second limiting mechanisms limit displacement of the connecting blocks and the vertical beams.