The invention provides a hydraulic double-type crane which comprises a gantry unit, a skidding unit and dismounting and mounting units, wherein the gantry unit comprises gantry top sections, at least one gantry standard section connected to the lower parts of the gantry top sections as well as gantry bases connected below the gantry standard section; the dismounting and mounting units are connected to the gantry bases and comprise gantry self-dismounting and mounting systems and jacking sleeve frames; and the skidding unit is connected above the gantry top sections and comprises a skidding beam, a skidding bearing beam and a skidding beam skidding mechanism which can drive the skidding beam to skid on the skidding bearing beam. According to the hydraulic double-type crane, no-load and loaded skidding of the skidding beam can be achieved, and the skidding beam span can be adjusted.