PURPOSE: Kawasaki disease(KD) is known as one of the most important causes of acquired heart disease in children. But the incidence of acquired heart disease can be reduced by early diagnosis and treatment with large amounts of intravenous gamma-globulin(IVGG). For early diagnosis and treatment of atypical KD, we analyzed and compared the clinical features, laboratory findings and coronary lesions in patients with typical or atypical KD. METHODS: A retrospective chart review was conducted in all children with Kawasaki disease who were admitted to the Department of Pediatrics of Kwang-Hye Hospital between January 1998 and December 1999. Except for 15 cases who were not followed, 62 cases were involved in this study. We analyzed and compared the clinical features, laboratory findings and coronary lesions in patients with 39 typical cases and 23 atypical cases of KD. RESULTS: The lowest incidence among clinical symptoms was cervical lymphadenopathy in both groups. In atypical cases, cervical lymphadenopathy, polymorphous exanthema, and changes of peripheral extremities were significantly lower than in typical cases. The duration of fever was similar in both groups, the mean defeverescence time after administration of IVGG in atypical cases was significantly shorter than typical cases(atypical, 2.6 days, typical cases, 1.8 days). The coronary artery dilatation appeared in 4 cases(17.4%) of atypical and 17 cases(43.6%) of the typical group. In most cases of both groups, left coronary artery dilatation was detected. CONCLUSION: To decrease the incidence of serious coronary complications due to atypical KD, careful evauation of clinical findings, early study of echocardiography and early infusion of large doses of IVGG are needed.