Abstract: The welding parameter monitoring and tracking control system of arc sensor was developed with LabVIEW. Arc sensor tracking monitoring system based on the virtual instrument was disscussed. This instrument possessed the ability to analyze on-line and display of electrical parameter wave of the arc sensor. It could control the rotating torch scanning velocity and welding speed as well as implement logical control. Design method and the control flowchart of the arc sensor tracking and monitoring software were realized using LabVIEW.