Abstract： Objective： To observe the effects of crocin on thyroid autoantibodies and thyroid hormone levels in Hashimoto thyroiditis (HT) model rats. Methods：A total of 21 SD rats were randomly divided into three groups， with seven rats in each group. The blank control group was fed with distilled water； the model group was prepared with HT model，and given intragastric treatment of the same amount of distilled water. The crocin group was prepared with HT model，and was given intragastric treatment of 20 mg/kg of crocin once a day. At the 8th week， serum levels of anti-thyroid peroxidase antibody (TPO-Ab)， antithyroglobulin antibody (TG-Ab)，free triiodothyronine (FT3)，free thyroxine (FT4)，oxidative stress markers reactive oxygen species (ROS)， superoxide dismutase (SOD)， glutathione (GS) were detected by ELISA. Results： Compared with those in the blank control group， the levels of serum TPO-Ab， TG-Ab， FT3， FT4 and ROS in the model group were increased (P＜0.05)， while the levels of SOD and GSH were decreased (P＜0.05). Compared with those in the model group， the levels of serum TPO-Ab， TG-Ab， FT3， FT4 and ROS in the crocin group were reduced (P＜0.05)， while the levels of SOD and GSH were enhanced (P＜0.05). The results of Pearson correlation analysis showed that the levels of serum SOD and GSH were negatively correlated with TPO-Ab and TG-Ab (P＜0.001). and that ROS was positively correlated with TPO-Ab and TG-Ab (P＜0.001). Conclusion： Crocin can effectively reduce the oxidative stress levels in HT rats，inhibit the increase of TPO-Ab and TG-Ab，and improve the thyroid dysfunction. The mechanism of action may be related to the anti-oxidative stress.