Abstract: Based on diffusion dynamics, U₃Si₂-Al interdiffusion layer growth model and fuel swelling model under irradiation condition were established. With fuel irradiation test data for China ENgineering TEst Reactor（CENTER）, the validity and applicability of the models all above were demonstrated. The results showed that the interdiffusion layer growth model agrees well with the post-irradiation measured data now available, and could be used in the calculation of U₃Si₂-Al fuel swelling characteristics; the fuel swelling model is conservative for the swelling prediction for CENTER fuel element.