Objective To disuss the clinic characteristics,the etiologies and the misdiagnosis cause of hyperthyroidism featuring in vomit mainly.Methods The clinic data of 35 hyperthyroids featuring in vomit mainly were reviewed and analyzed.Results The hyperthyroids in this group were middle-aged female mainly whose symptoms showd that they vomit frequently with abdominal distention,thin,inappetence,chest congestion,palpitation;tachycardia;hypohepatia and electrolyte disturbance.Furthermore,their thyroid gland function assay is in concordance with the hyperthyroidism diagnosis.Treatment for antihyperthyroidism can get remarkable effects.Conclusion The patient showing vomit of unknown origin may be taken into account as hyperthyroid.The key points to prevent misdiagnosis are to detect thyroid gland function in time and to improve the understanding for un-typical hyperthyroidism.