To investigate the influences of applied shear stress on the nucleation process and micro-texture formation of α precipitates, β→α transformation in Ti-6Al-4V alloy was simulated by phase field method using Pandat software and JmatPro (TTT-Ti) databases as direct input in the model. The effects of applied positive and negative shear stresses (10, 30 and 50 MPa) along (101)[-111]β or (12-1)[-111]β on the microstructure evolution of Ti-6Al-4V alloy were explored under aging at certain temperature. The results show that. with the increase of shear stress, the elastic interaction between applied stress and α variants gradually plays more significant role in determining the microstructure of the system under certain undercooling, t herefore, the selection of α variants is gradually enhanced. It was found that the shear stress has a stronger effect on the variant selection than that of normal stress, therefore maybe more effective on microtexture formation. With the increase of shear stress, two or one type of variant are selected under positive shear, and one type of variant is favored by the negative shear along (101)[-111]β or (12-1)[-111]β respectively.