Abstract: Objective To investigate clinical efficacy of levothyroxine combined with low dose methionazole on the treatment of Graves’ hyperthyroidism. Methods 162 cases of Graves’ hyperthyroidism were randomly divided into the control group (low dose of methimidazole treatment, 79 cases) and the observation group (thyroxine + low dose of methimidazole treatment, 83 cases). The control group was given small dose methimazole, the initial dose 10~20mg/d, 1 times/d, 3 months later, gradually reduced the dose to 2.5~7.5mg/d maintenance according to condition of the patients. On basis of the control group’s treatment, the observation group was given levothyroxine (25μg/d and 2 times/d). Observe and compare the 2 groups of patients’ thyroid function indicators before and after treatment, adverse reactions in the treatment process and the recurrence after treatment. Results At 12 months of treatment, compared with the control group, the thyroid function indexes of the observation group were significantly improved (P < 0.05), the effective rate was significantly higher (P < 0.05), and the incidence of adverse reactions were no significant difference (P > 0.05). After the treatment, the recurrence rate was significantly lower in the observation group than in the control group ( P < 0.05). Conclusion Levothyroxine combined with low dose methionazole on the treatment of Graves’ hyperthyroidism has good clinical efficacy, high safety and low recurrence rate