Titanium alloys (Ti-alloys) have complicated multiscale hierarchical structures that enabled a variety of ex-cellent mechanical properties, such as strength, ductility, fatigue and creep resistance etc. But how are the microstructures formed under different conditions, and what are the inter-dependencies between the properties and various microstructures are not easy to reveal solely by experiments. In the last two decades, multiscale modeling and simulation have been carried out, and promoted our understanding of the microstructure for-mation and their deformation mechanisms. In the present paper, recent progresses are reviewed and future trends analyzed, on the simulation of microstructure evolution in Ti-alloys and how these are combined with experimental characterization and verification, to reveal the controlling factor and hidden mechanism under various deformation/transformation conditions; and to promote the optimization of thermo-mechanical pro-cessing. It is recognized that, future computations should pay more attention to the bottleneck problems in the design and application of Ti-alloys and play a more important role in identifying specific controlling factors and revealing the relevant working mechanisms in more complicated process, such as thermo-mechanical processing, powder metallurgy or additive manufacturing. In addition, artificial intelligence (AI) may assist the screening of new materials. These efforts may accelerate the development and application of new alloys, and at lower cost, especially for Ti-alloys in aero/space engine satisfying multiple performance requirements such as strength, toughness, creep resistance, fatigue life and other properties.