Kawasaki disease is an acute febrile illness typically elicited by vasculitis and occurring in young children. We investigated the polymorphism of the angiotensin-1 converting enzyme (ACE) gene in children with Kawasaki disease and also in age-matched controls. A total of 107 children, with a mean age at diagnosis of 1.71 ± 1.48 years, who suffered from Kawasaki disease and who were treated with aspirin as well as intravenous immunoglobulin were enrolled in this study. Control subjects consisted of 107 children, with a mean age of 1.84 ± 1.20 years. The polymorphisms of the ACE gene, including I/D, A-240T, and G2350A, were examined using a polymerase chain reaction method for Kawasaki disease patients and also for control subjects. We noted a significant difference in the distribution of the ACE gene I/D genotype between Kawasaki disease and control groups. The ACE gene G2350A polymorphism and associated allelic frequencies demonstrated an association with Kawasaki disease. Our results revealed no evidence of any association between the ACE gene polymorphism and the frequency of coronary artery aneurysm associated with Kawasaki disease, although our results do support a role for the I/D and G2350A polymorphism of the ACE gene in determining the risk of Kawasaki disease in the population of Taiwan.