Objective: To study the influences of dihydrotestosterone (DHT) on the development of experimental autoimmune Graves disease (EAGD), and to observe the effect of DHT on cytokines in male BALB/c mice model. Methods: Male BALB/c mice aged 6-8 weeks were divided into 4 groups using random number table: (1) control group; (2) EAGD group; (3) placebo group; (4) DHT group. EAGD mice were induced with an adenovirus expressing the human thyroid stimulating hormone receptor antibody A-subunit (Ad-TSHR289). DHT (5mg) or a matching placebo were implanted one week before the first immunization. Thyroid hormones were detected with radioimmunoassay kit.. Cytokines [such as interferonγ (IFNγ), interleukin (IL)-4, IL-10, IL-9, and IL-17] producing cells from the spleen were detected using flow cytometry. Results: As expected Ad-TSHR289 treatment increased total thyroxine [EAGD group vs. control group: (117.76±32.69) nmol/L vs. (33.08±12.61) nmol/L, P<0.0001] and free thyroxine [EAGD group vs. control group: (15.01±11.55) pmol/L vs. (3.55±1.88) pmol/L, P<0.0001]. Treatment of DHT slightly lowered thyroid hormones [DHT group vs. placebo group: total thyroxine (114.80±44.27) nmol/L vs. (123.17±77.73) nmol/L; free thyroxine (13.48±6.01) pmol/L vs. (14.19±12.65) pmol/L], without significant difference (all P>0.05)]. However, the percentage of IL-10, but not IFN γ, IL-4, IL-9 and IL-17, secreted spleen cells increased in DHT group than in the placebo group [(7.11±3.29)% vs. (3.51±1.36)%, P<0.05]. Conclusion The effects of DHT on thyroid hormone are mild. It might play an immunomodulatory role in the male mouse Graves disease model by up-regulating the cytokine IL-10.