Persistent hiccup is a rare but potentially severe condition that can be symptomatic of a variety of diseases or idiopathic. Most episodes last only a few minutes and are self-limited, but hiccup can get persistent and become a real problem for physician and patient alike. T he center of hiccup may be activated by a great variety of stimuli travelling along different nerve pathways and bring different effecter responses. We report a case of persistent hiccup as a presentation of impending thyroid storm of Graves' disease. Though the condition is rare, clinicians should remain alert to the possibility of this diagnosis.