Based on an analysis which has been made of the multiple cutting process of CNC wire cutting machines, it is considered that the main reason affecting product quality is the poor dynamic stability of molybdenum wires in operation. The main factors affecting the dynamic stability of molybdenum wire are radial run-out and axial movement of guide wheel, radial run-out of wire storage cylinder, jitter of molybdenum wire between upper and lower guide wheels, uneven pre-tightening force during wire winding, etc. Measures to be taken to reduce the jitter of molybdenum wire include breaking off the transmission path of the runout of guide wheel, reasonably controlling the running speed of molybdenum wire, adding the tensioning device of molybdenum wire, etc. The theoretical analysis and experimental results show that the multiple cutting process can be carried out on WEDM machine by improving the CNC WEDM machine tool and adopting appropriate process methods, with the product quality meeting the requirements.