The invention provides a folding engineering ladder which comprises a ladder body, a folding bracket and a supporting frame. The ladder body includes two parallel armrest frames arranged at an interval, and a plurality of pedal platforms arranged at intervals are connected from top to bottom between the two armrest frames; the upper end of the folding bracket can be rotatably connected with the two armrest frames, and the folding bracket is provided with an unfolding position for supporting the ladder body and a folding position that fits with the armrest frames; and the upper end of the supporting frame can be detachably connected to the two armrest frames, when the folding bracket is in the state of being located at the unfolding position, the lower end of the supporting frame can be detachably connected to the lower end of the folding bracket, and when the folding bracket is in the state of being located at the folding position, the lower end of the supporting frame can be detachably connected to the lower part of the ladder body. The folding engineering ladder can be completely folded and in a closed state, space is effectively saved, moving, storage and vehicle transportationare convenient, the structural stability is high, and it is ensured that maintenance personnel can safely and conveniently complete aircraft maintenance work.