The invention discloses a mechanical recirculating ball type electric power steering device, which is mainly composed of a direct-current brushless motor, a controller, a sensor, a worm and gear pair,a steering screw nut pair, a rack sector pair and a shell. The steering screw nut pair of a key transmission mechanism adopts an end face circulation mode and is composed of a steering screw, a steering nut, reversers, check rings and a steel ball, and an inner roller path of the steering nut and an outer roller path of the steering screw are combined to form a working roller path of the steel ball. The reversers are embedded in two ends of the steering nut respectively and are axially limited through the check rings. According to the structure, the bearing capacity of the steering screw nutpair is obviously improved, load distribution is even, the structure is stable and firm, the weak link of reversing impact does not exist, the space structure is compact, operation is flexible and smooth, the machining manufacturability is good, and a better use prospect is achieved.