In this paper, the evolution of the He-related defects in the titanium film is experimentally investigated by combining slow positron beam analysis (SPBA) and transmission electron microscope (TEM) technique. The results indicate that small bubbles in the titanium film distribute uniformly at room temperature. With the increment of He concentration, the density of He bubbles in the sample increases correspondingly. Large bubbles are observed in the titanium film containing high He concentration after 973 K high temperature annealing, and it is found that both migration-coalescence and cascade-coalescence around the bigger He bubbles lead to the rapid growth of He bubbles.