The invention discloses a processing technique of screw threads with coarse-pitch, which pertains to the technical field of mechanical process. The processing technique adopts the numerically controlled lathe with thread processing function, based on which the inner and outer thread with coarse-pitch is made, and the processing technique comprises the steps that: 1) starting point controlling technique, 2) the rough processing technique of the layering dissection, 3) precise processing and forming technique of locus method of thread section points. The processing technique of the external teeth shape thread of rotator is that: 1. deciding a datum mark, caving a baseline, setting a right place for cutter point, 2. carving a thread line and checking according to drawing paper, 3. adopting a 90 degree of boring cutter which is provided with a diamond coarse blade of 35 degree and adopting the method of layering dissection, a coarse thread groove to ensure peripheral reside of 1mm, 4 using the same tool cutter the blade of which is changed into a precise blade and adopting the precise processing and forming technique of locus method of thread section points to semi precisely process and precisely process thread surface, 5. testing the teeth adopting the teeth section template and testing the teeth distance by using the teeth distance template.