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In order to understand the non-isothermal transformation behavior of Ti-6Al-4V titanium alloy in the continuous heating stage of solution treatment, thermal dilatometry tests with heating rates of 0.1~0.8 &#176;C/s were designed. The conversion between the expansion amount and the transformed volume fraction was realized by the lever principle, and the transformation characteristics of &#945; + &#946; &#8594; &#946; were quantified based on the Kissinger-Akahira-Sunose (KAS) theory and the modified Johnson&#8722;Mehl&#8722;Avrami (JMA) model. The results show that the phase transformation kinetics curves present typical &#8220;S&#8221; patterns, and the element diffusion transformation controls the nucleation and growth of new grains during the transformation of &#945; + &#946; &#8594; &#946;. The phase transformation interval gradually moves to high temperature regions with the increase of heating rates, and the phase transformation activation energy is 445.5 kJ&#183;mol^&#8722;1. The phase transformation process is divided into three stages according to the relationship between the Avrami exponent <i>n</i> and the transformed volume fraction <i>f</i>_T. These three stages correspond to different stages of grain nucleation or growth.