ABSTRACT Objective: To describe the case of an infant - diagnosed with incomplete Kawasaki disease - who developed BCG scar reactivation. Case description: A 6-month-old patient was admitted to hospital with fever associated with ocular hyperemia, cervical lymphadenopathy, and hyperemic lips, and remained hospitalized for 12 days. The physical examination revealed an inflammatory reaction at the site of the BCG scar, leading to the diagnosis of incomplete Kawasaki disease. The patient was treated with venous immunoglobulin, but presented recurrence of Kawasaki disease, with subsequent onset of coronary artery disease. Comments: BCG scar reactivation is an important finding in countries where the vaccine is routinely given and may be a useful marker for early diagnosis of Kawasaki disease, especially in its incomplete form.