Abstract: Aimed at the problems of low positioning accuracy, poor coaxiality, and low welding efficiency in precision laser welding of thin-walled pipes, a precise laser welding fixture for thin-walled pipes has been designed. According to the laser welding process analysis of thin-walled round pipes, these following parts of the fixture have been designed, including the supporting spindle, the rear positioning plate, the front positioning plate, the radial positioning clamping device assembly and the axial adjustment device. On the premise of ensuring the welding quality of the round pipe, the fixture can be adjusted according to the diameter and length of the round pipe to be welded to ensure the coaxiality and axial size of the round pipe welding, so as to reduce labor intensity and improve welding efficiency.