The invention relates to a multi-stage prop-open type pipeline shaper. The multi-stage prop-opening type pipeline shaper is used for shaping repairing of instable pipelines, locally deformed pipelines and deformed barrel bodies. According to the technical scheme of the multi-stage prop-opening type pipeline shaper, an outer barrel is arranged at one end of a front end cover, and a front end oil cylinder is arranged at the other end of the front end cover; a back pedestal is arranged at the other end of the front end oil cylinder, an outer end oil cylinder is arranged at the other end of the back pedestal, and a front pedestal is arranged at the other end of the outer end oil cylinder; front rolling wheels are hinged between the front pedestal and the back pedestal through connecting rods, and back rolling wheels are hinged between the back pedestal and the front end cover through connecting rods; one end of a middle oil cylinder is fixed to the front end cover, and the other end of the middle oil cylinder is fixed to an inner barrel through a mounting plate; and a T-shaped groove is formed in the back end cover in the radial direction, slips are arranged in the T-shaped groove, and back end oil cylinders are arranged between the back end cover and the slips. According to the multi-stage prop-opening type pipeline shaper, the rolling wheels are used for shaping so that the damage, caused by the rolling wheels, to a deformed pipe section can be lowered; and multi-stage prop-open is applicable to the shaping operation of the largely-deformed and seriously-instable pipelines.