The invention discloses manufacturing equipment of polyester spunbonded non-woven fabric with high filtering precision and a method of the equipment. The equipment comprises a mixing tank, a crystallizer, a drying tower, a screw extruder, a first spinning box, a second spinning box and a third spinning box; water-soluble polyester slices and partial polyester slices pass through the mixing tank, the crystallizer, the drying tower, the screw extruder and the second spinning box in sequence, and spinneret orifices of a spinneret plate of the second spinning box are of an annular structure; another part of polyester slices pass through the crystallizer, the drying tower, the screw extruder, the first spinning box and the third spinning box in sequence; the second spinning box, the first spinning box and the third spinning box are all connected with a drafting nozzle, and the drafting nozzle is connected with a web forming device, a spunlace reinforcing device, an alkaline liquor immersiontreatment device, a washing device and a drying device in sequence. Through a multi-box spinning technology, the upper and lower face layers of the non-woven fabric have good mechanical performance,and the middle layer has good filtering precision.