Acute epiglottitis is an inflammatory, edematous disease of the epiglottis and adjacent structures, usually caused by Haemophilus influenzae type b. It is a life-threatening condition, occurring mainly in childhood. There have never been any reports of this condition in Taiwan. We report a case of 4-year-old boy who presented with characteristics of systemic illness combined with respiratory distress on arrival at the emergency room. His mouth was open and his neck was hyperextended. The diagnosis of epiglottitis was established on the basis of physical examination, lateral neck x-ray, and the finding of an enlarged, swollen, erythematous epiglottis on flexible fiberoptic laryngoscopy. Urine latex agglutination test for H. influenzae type b was positive and a blood culture grew H. influenzae type b. He was treated with cefotaxime and did not require intubation.