The phase distribution and evolution characteristics of titanium forged parts influenced by hot forging and subsequent air cooling procedures have an essential effect on the ones of final parts, resulting in a direct impact on their ultimate mechanical properties. This study presents a simple and effective modelling approach to predict the transformation characteristics of temperature and phases during Ti-6Al-4V drum hot forging and air cooling processes. In particular, 2D FE half-symmetry models coupling with phase transformation equations are developed, and then verified by experiments. Subsequently, the distributions of temperature and phases within the forged and cooled drums are numerical investigated in details. Finally, their temperature and phase evolutions in terms of general level and distribution uniformity are analyzed quantitatively. The results indicate that the distributions of different phases within the forged and cooled drums are extremely inhomogeneous, which are related to temperature variations. Besides, the a phase distribution within the forged drum remains constant in the subsequent air cooling operation, which is related to cooling rates. (C) 2020 The Author(s). Published by Elsevier B.V.