The lateral vibration of the electrode wire during High Speed Wire Electrical Discharge Machining (HS-WEDM) is an important factor affecting the processing quality, which restricts its further application development. Based on this, the causes and influencing factors of the electrode wire vibration are analyzed, and an intelligent tension control system is designed. By detecting the gap voltage and gap current in the gap discharge process, the fuzzy algorithm was used to judge the gap discharging state in the sampling period. In the discharge state, then the ratio of the spark rate in the gap discharge state was applied twice to obtain the feed amount required for the wire mechanism. It has been verified by experiments that this method can reduce the vibration of the wire by tension control, and reduce the surface roughness and dimensional error of the workpiece by 13.4% and 9.5%, respectively, effectively improving the processing quality of HS-WEDM.