Dynamic recrystallization microstructure evolution of titanium alloy TA15 was investigated during deformation at 1050 oC and different strain rates. The dynamic recrystallization kinetics, nucleation rate and grain size evolution were discussed. Results show that with different strain rates there are two types of dynamic recrystallization, i.e. the continuous and the discontinuous. According to the dynamic analysis, at the strain rates of 0.01, 0.1 and 1 s-1, the corresponded dynamic recrystallization steady strains are 1.26, 1.57 and 2.93, indicating higher strain rates lead to higher steady strain. It is hard to reach steady stage at higher strain rates while the nucleation is obviously higher than that at lower strain rates. At lower strain rate, a slight increment of strain rates can greatly decrease the grain size; however, at higher strain rates, the grain size is little dependent on the strain rates. Therefore, refinement of structure can be obtained by the continuous dynamic recrystallization at high strain rate and large strain.