Diabetic ketoacidosis (DKA) is a life-threatening complication of diabetes in children. According to a recent study in Korea, the number of patients with DKA is increasing. We aimed to examine the clinical characteristics of children with DKA. We retrospectively reviewed the medical records of 31 patients admitted with a diagnosis of DKA during a period of 13 years (1995 to 2007) in Chonnam National University Hospital. DKA in children most commonly occurred between 12 and 14 years of age (41.9%). A total of 14 patients (45.2%) had a prior history of diabetes, whereas DKA was the initial presentation in 17 patients (54.8%). The most common precipitating factor of DKA was omission of insulin treatment in children with diabetes. Consciousness status was not correlated with laboratory values such as pH, bicarbonate, glucose, or dehydration status (BUN/Cr ratio). Also, the severity of DKA was not correlated with the admission period. Skipping insulin treatment was the most common precipitating factor of DKA. More proper education and efforts of health care providers are required to prevent DKA in children with diabetes. DKA was the initial presentation in many patients; therefore, it is necessary to conduct aggressive evaluation for early diagnosis and treatment.