Titanium alloys are widely used in the aerospace field due to their high strength, low density, corrosion resistance and other excellent properties. Therefore, it is necessary to theoretically study the evolution of titanium alloys for the quantitative design of new titanium alloys. In this paper, using the valence electron structure parameters calculated by Yu's theory, combined with the rules of cellular automata, a simulation method of the Ti?2Nb alloy β?phase solid solution microstructure was established, and he microstructures of Ti?2Nb alloys at 1 000, 1 050, 1 100, 1 150 and 1 200 ℃ were simulated. The research results show that the model method can associate the phase structure unit with the nucleation and growth of the β microstructure; the quantitative relationship between the number of nucleation points in theβmicrostructure and the solid solution temperature can be characterized by the binding energy of the phase structure unit calculated by Yu's theory; the evolution of the grain size of the β?phase microstructure with the solution time can be correlated by the simulation step. These studies can provide a reference for the establishment of a quantitative relationship between alloy composition， preparation process， structure， performance.