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The residual stress of Ti-3Al-2.5V tube, which was manufactured by different thermal-mechanical processes, has been investigated. XRD was applied to measure the residual stress based on the shift of the peak of diffraction profiles. The results show that the residual stress values of Ti-3Al-2.5V tube under the certain fabrication parameters are all positive, whereas the values after the process change are negative. It means that the former one is tensile stress, which is opposite to the latter’s compressive stress. There is an obvious difference in fabrication process between them. Because the compressive stress can benefit the fatigue life and stress corrosion resistance, the tensile stress should be avoided in tubing production.