Aiming at present problems of hydraulic station pipe manual welding for low welding efficiency、poor welding appearance and harsh working conditions and others, research on intelligent robot welding technology for hydraulic station pipe is carried out. Through a complete set of robot arc-welding system built already, the research content included three aspects as the robot welding process test, welding seam tracing technology and flexible fixture design were developed. At present, some research results have been applied to actual production.