Titanium alloys are critical structural materials with excellent comprehensive properties such as high specific strength, excellent toughness, and high corrosion resistance. These properties of titanium alloys can be tuned by the manipulation of microstructure evolution during a variety of heat treatment. In this work, we used the advanced scanning electron microscopy (SEM) and MIPAR image analysis software to quantitatively study the microstructural evolution in the Ti-6Al-4V (wt.%, Ti-64) alloy. The Ti-64 alloy samples were heat treated at 1000°C for 30 mins and then cooled to room temperature using different cooling methods, including water quenching, air cool, or furnace cool. The bimodal α microstructure, martensitic microstructure, and colony α microstructures have been characterized using SEM backscattered imaging. The morphology, size and fraction of each α microstructure have been quantified using MIPAR. This work has been supported by the University of Nevada Reno seed grant.