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TA18 titanium alloy tubes based on cold pilgering are widely used for the hydraulic system of airplanes and spacecrafts and drill pipes of oil exploration due to their high specific strength, good cold processability and reasonable texture distribution. In this study, according to the mechanical analysis of multi-strokes cold pilgering process, precision motion mode and stress state of the tube during the forming process were obtained. Furthermore, a three-dimensional FE model of multi-strokes cold pilgering of TA18 titanium alloy tube was developed in the FE software environment of ABAQUS/Explicit. Some key modeling techniques were proposed, including the implementation of virtual crank-connecting-link device, the control method of multi-strokes motion modes, the definition of complex geometric formation and the definition of rolling friction and sliding friction. The FE model was validated by energy conservation principle and experimental results, and evaluated by the distributions of equivalent stress and equivalent plastic strain during the forming process.