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The hot deformation behavior of TB8 titanium alloy with a lamellar α structure in the α+β dulex phase region was investigated. The results show that at the strain rate of 1 s^-1, a continuous flow softening phenomenon is observed in the curve of the samples deformed at 650 ℃, while a discontinuous yield phenomenon is visual in the curve of the samples when the deformation temperature is higher than 650 ℃. The discontinuous yield phenomenon is gradually disappeared with increasing deformation temperature and strain rate. When the strain rate is 0.001 s^-1 and the deformation temperature is 750 ℃ as well as 800 ℃, typical characteristics of dynamic recrystallization is presented in the curve of the samples. The relationship among peak stress <i>σ</i>_p temperature <i>T</i> and strain rate <i>ε</i> · and is characterized by Arrhenius-type constitutive equation. The equation between the material constants (<i>α</i>, <i>Q</i>, <i>n</i> and ln<i>A</i>) and strain is constructed. The effect of strain on the material constants (<i>α</i>, <i>Q</i>, <i>n</i> and ln<i>A</i>) of the Arrhenius-type constitutive equation is analyzed. The value of α is increased with true strain, while the values of <i>Q</i>, <i>n</i> and ln<i>A</i> are gradually decreased. The correlation coefficient (<i>R</i>²) and the AARE value between the experimental and the predicted stress are 0.945 and 9.08%, respectively. This indicates that the strain-compensates Arrhenius type constitutive equation can better predict the flow stress value under different deformation conditions for the TB8 titanium alloy with a lamellar α structure deformed in the α+β dulex phase region.