The invention relates to a peristaltic downhole tractor which comprises a cylindrical body, an inner cylinder and a piston rod, wherein the cylindrical body is connected with a string, the inner cylinder is arranged in the string to form a piston cavity and a main runner, and the piston rod extends out from the piston cavity. A first end of the piston rod is connected with a piston positioned in the piston cavity, and an anchoring component connected with a drilling component is arranged at a second end of the piston rod. According to the peristaltic downhole tractor, stable traction can be generated, the direction of the traction is determined, and drilling of a drill bit is boosted.