The invention relates to an integrated electric cylinder based on a reverse type planetary roller screw, belongs to the technical field of electric cylinders for aerospace, and solves the problem that the existing electric cylinder cannot realize high-precision position closed-loop control and has no fault tolerance function of a servo motor. And it is necessary to limit the rotation of the push rod by the load. The integrated electric cylinder of the present invention is composed of a cylinder block, a bearing, a stator winding, a rotor permanent magnet, a nut sleeve, a roller screw, an encoder, an encoder mounting frame, an encoder mounting shaft and a magnetostrictive displacement sensor; the cylinder The body includes a casing, an end cover and a guide sleeve, and the end cover and the guide sleeve are respectively arranged at both ends of the casing; the bearing is sleeved in the casing, and the nut sleeve is sleeved in the bearing; the nut sleeve is connected with the roller screw ; The casing is connected with the stator winding, and the rotor permanent magnet is arranged on the outer surface of the nut sleeve. The present invention can realize high-precision position closed-loop control, the stator windings are mutually redundant, and there is no need to increase the push rod to limit the rotation of the lead screw.