Diabetic ketoacidosis (DKA) is a complex metabolic state characterized by hyperglycemia, metabolic acidosis and ketonuria. Cerebral edema is the most common rare complication of DKA in children. The objective of the study was to emphasize the importance of careful evaluation and monitoring for signs and symptoms of cerebral edema in all children undergoing treatment for DKA. We present a case of 11-year-old girl with a history of diabetes mellitus type I (T1DM) who presented with severe DKA complicated by hypovolemic shock, cerebral edema and hematemesis. Considering the fact that complications of DKA are rare and require a high index of clinical suspicion, early recognition and treatment are crucial for avoiding permanent damage.