Base　on　the　wave　controlling,　a　fuzzy　control　system　of　welding　arc　self-sensing　for　synergic　CO2　short　circuit　arc　welding　is　discussed.　On　the　base　of　the　relationship　among　the　various　welding　parameters,　the　automatic　setting　and　adjusting　of　welding　parameters　is　realized　in　above　system.　The　result　of　experiences　shows　that　this　fuzzy　control　system　cause　a　stable　short　circuit　arc　welding　process　with　much　lower　spatter,　better　profile　of　the　weld.