A new method for assessing the local shear strain in adiabatic shear band (ASB) of Ti-6Al-4V is proposed by using of gradient-dependent plasticity. The maximum local plastic shear strain (MLPSS) in the ASB depends on the critical plastic shear strain, the gage length of Ti-6Al-4V specimen, the total thickness of the ASB and the average plastic shear strain in the ASB. Results show that the MLPSS in the ASB decreases nonlinearly with the increase of the total thickness of the ASB. When the total thickness of the ASB approaches 1mm, although the methods for determining the critical plastic shear strain are different, the calculated values for MLPSSs in the ASB almost remain unchanged. When the total thickness of the ASB is in the range of 0.335~1 mm, the calculated values for MLPSSs in the ASB are found to be in the range of the lower bound (75%) to the upper bound (350%) of the experimental results obtained by Liao and Duffy (1998).