Abstract: A DSP-based real-time seam tracking system for PAW stainless welded pipes is presented here in the paper with details concerning such main aspects as the working principle,and the design tips of both software and hardware of the control system,etc.The laser sensor is used in this system to measure the position of the seam,and the Fuzzy-P double-mode control technique is adopted to rectify deviation of the seam.The DSP is used as the central controller to produce control signal which drives the motor for vertical movement of the welding torch,and makes the welded pipe rotating so as to realize the real-time automatic seam tracking with the welding torch,and the adaptive speed control according to the weld seam dimensions.The results of the experiments demonstrate that the said system is capable of bring about the real-time automatic seam tracking of the welding pipe by the welding torch,having completely met the requirement for the welding operation.