Abstract: Objective To investigate therapeutic application of eukaryotic expression vector pcDNA3.1(+)/hFasL in animal model for TAO. Methods Three groups were set in this study. Animals in control group (10 mice) were immunized with splenocytes sensitized by blank plasmid pcDNA3.1(+), and then treated with pcDNA3.1(+). Animals in treated group (19 mice) and model group (19 mice) were all immunized with splenocytes sensitized by hTSHR, then the former were injected behind the eyeballs with pcDNA3.1(+)/hFasL, while the latter had no special treatment. Results 52.6％ in model group displayed obvious edema, hyperplasia of adipose tissue, focal degeneration and disruption of muscular fibers in their orbital tissues, and when compared with the control group, elevated TT4 and reduced TSH levels (p<0.05) were also observed. In treated group, only 15.8％ showed changes of TAO with apoptosis was found, and there was no statistical significance in levels of TT4 and TSH between treated group and control group. TRAb levels were not statistically significant among the three groups. Conclusion Retrobulbar injection with the plasmid coding for hFasL has made a curative effect on TAO in mice. These results indicated the therapeutic potential of gene therapy via Fas/FasL-mediated pathway for TAO.