Under variations of bending radii and material properties, the multi-defect constrained formability of thin-walled commercial pure titanium (CP-Ti) tube is identified to explore the forming potential of this advanced lightweight material via explicit/implicit 3D-FE models and the experiments. The major results show that: 1) The variations of hardening exponents, thickness anisotropy exponent and Young’s modulus, have great effects on bending formability; 2) Compared with the wall thinning and cross-section deformation, the wrinkling instability is the dominant defect to restrain the bending formability of the large diameter thin-walled (LDTW) CP-Ti tube. The bending formability of CP-Ti tube, especially the anti-wrinkling capability, can be improved at elevated temperatures.