Diabetic ketoacidosis (DKA) is caused by absolute or relative lack of insulin. Lack of insulin leads to hyperglycemia, ketonemia, and acidosis. Prevalence of DKA at diagnosis of type 1 diabetes (T1D) varies around the world from 18 % to 84 %. Incidence of recurrent DKA is higher among females, insulin pump users, those with a history of psychiatric or eating disorder, and suboptimal socioeconomic circumstances. DKA is the most common cause of death in children with T1D. Children with DKA should be treated in experienced centers. Initial bolus of 10-20 mL/kg 0.9 % saline is followed by 0.45 %-0.9 % saline infusion. Fluid infusion should precede insulin administration (0.1 U/kg/h) by 1-2 hours. The prevention of DKA at diagnosis of diabetes can be achieved by an intensive community intervention and education of health care providers to raise awareness. Prevention of recurrent DKA requires continuous patient education and access to diabetes programs and telephone services.