The welding wire feed mechanism is an important component of welding equipment, both reliability and stabilization are the premise that the welding quality can be ensured.The PID is currently adapted to control the welding wire feed mechanism,although the fuzzy PID has advantage of fast response and adaptation,the precision of fuzzy PID is lower.Accordingly,the fuzzy self-adaptive PID controller was proposed through changing fuzzy input variables and output variables based on variable universe,simple function is adopted as scaling factor,the fuzzy PID controller parameters are adjusted to improve the precision and adjustment range.Simulation results show that control effects of fuzzy self-adaptive PID adopted by the welding wire feed mechanism have good adaptive ability and robustness based on variable universe, the welding experiments indicate that the welding quality met the requirements actually.