The model suggested by Ashby and Coble was used to analyze the sintering process of pure titanium in this paper. Then based upon this result, homogenizing behavior of alloying elements of aluminum and iron during sintering was further discussed for bio-titanium alloy Ti-5A1-2.5Fe. Using this method, the concentration variation of alloying elements was calculated to indicate the effect of element diffusion on the structure transformation. It was shown that the calculated results were in agreement with the results obtained in the previous experiments.