Abstract: Objective:To explore the effects of different drug therapy on the thyroid hormone level in patients with schizophrenia.Methods:One hundred and twenty patients with schizophrenia were randomly divided into group A(treatment with azole),group B(treatment with quetiapine) and group C(treatment with risperidone)(40 cases each group).The thyroid hormone levels in 3 groups between before treatment and after 1 month of treatment were compared.Results:The differences of the levels of three iodine thyroid glycine(T₃),four iodine glycine(T₄),free three iodine thyroid original glycine(FT₃) and free iodine thyroid original glycine(FT₄) between 3 groups before treatment were not statistically significant(P>0.05).After 1 month of therapy,the levels of T₃,T₄,FT₃ and FT₄ in 3 groups obviously decreased(P<0.01),and the lowest in group B(P<0.01),the level of FT₃ in group A was significantly lover than group C(P<0.01),and the differences of whose between group A and group C were not statistically significant(P>0.05).Conclusions:Azole,quetiapine and risperidone can reduce the thyroid hormone level in patients with schizophrenia,and the decreasing degree in patients treated with quetiapine is the most obviously.