To study the protective effect of “Yi Xiao Decoction” on serum and myocardial tissue of KKAy mice model，and discuss the possible mechanisms of its diabetic myocardial protection.Methods:The KKAy and C57BL/6J mice were randomly divided into the model group，normal group and the TCM group.The mice in different groups were administered distilled water and Yi Xiao Decoction，respectively by gavage.Specifically，the TCM group was fed with Yi Xiao Decoction，while the model group and the normal group were given distilled water.The expression of IGF-1 in serum was detected by ELISA，and expression of IGF-1 mRNA expressions in myocardia by RT-PCR after 4,8,12 weeks’ treatment.Results:In the different stages of the experiment，compared with the normal group，the expression of IGF-1 in serum and tissues in diabetic KKAy mice decreased significantly in the model group(P<0.01)，and compared with the model group，the expression of serum IGF-1 in TCM group in 8th weeks and 12th weeks increased significantly(P<0.05).The expression of mRNA IGF-1 in cardiac muscle tissue increased in 12th weeks.Conclusion:Yi Xiao Decoction can improve IGF-1 expression in serum and myocardial tissues and protect cardiac muscle tissue of the diabetic mice model.