In this study, we used fat-1 transgenic mice to explore the protective effect of endogenous n-3 PUFAs on liver injury in the model of autoimmune hepatitis induced by Con A. The results showed that fat-1 transgenic mice were resistant to Con A-induced hepatitis, which attributed to the suppressed T cell activation and Th1 differentiation in the presence of n-3 PUFAs. This evidence concerns the gene FAT1 and hepatitis A virus infection.