Titanium alloys are widely applied in aerospace, chemical and other related industries. The α+β alloys may obtain various microstructures and mechanical properties simply by varying their thermomechanical processing. Ti-6Al-4V alloy is the most common α+β titanium alloy. Its strength, ductility, fracture toughness and fatigue properties depend strongly on the microstructure especially texture. The understanding of the formation mechanisms of α micro-texture during processing is necessary for the optimization of the mechanical properties. In this work, the nucleation of α precipitates and micro-texture formation process under the influence of dislocations during the β→α transformation in Ti-6Al-4V alloy was simulated by phase field method. The stress field of an infinite straight dislocation was calculated by Willis-Steeds-Lothe method and used as input of the phase field model. It was shown that the normal stress component S₃₃ plays a dominant role in α variants nucleation in the presence of edge dislocation, while the shear stress component S₂₃ is the most important one for screw dislocation. The effect of edge dislocation on α variant selection is generally stronger than that of screw. V1 and V7 are the main variants selected by the edge dislocation while V7, V10 and V12 dominate around the screw dislocation, with V1/V7, V1/V4/V6 being the main variant cluster types around the edge dislocation, and V7/V10/V12 being the primary one for the screw dislocation. In a system with the presence of dislocations in the parent phase, the precipitate microstructure is determined by the combined effect of elastic interactions between the dislocation and different variants of a low symmetry precipitate phase, and elastic interactions among different variants. Variants with interfaces of relatively high energy may appear because of variants selection by dislocations.