Background and Objective: Diabetic ketoacidosis is one of the most common and life threatening complications in children with diabetes mellitus. The aim of this study was to evaluate predisposing factors, complications and prognosis of the patients with diabetic ketoacidosis admitted to Zanjan hospitals. Materials and Methods: The records of patients with DKA admitted to Mousavi and Vali-e Asr Hospitals of Zanjan city from 2006 to 2011 were studied. The presenting complaints along with laboratory results were collected and analyzed. Results: This study was carried out on fifty one patients with diabetic ketoacidosis. The mean age of children was 6.6±3.9 years. The most frequent symptoms were nausea and vomiting and the most frequent signs were dehydration (94.1%) and tachypnea (88.2%). Regarding laboratory results, 49% of patients showed hypokalemia, 25.5% hypoglycemia, 17.6% hyponatremia, 11.8% hypernatremia, and 9.8% hyperkalemia. Finally, 48 patients were discharged while 3 patients died two of whom were died due to cerebral edema. Conclusion: Cerebral edema was the major mortality factor in our study. Therefore, prevention and treatment of cerebral edema is recommended. References 1- Graham BB, Keniston A, Gajic O, et al. Diabetes mellitus does not adversely affect outcomes from a critical illness. Care Med. 2010 38: 16-24. 2- Berry D, Melkus GD. Epidemiologic perspectives of risk for developing diabetes and diabetes complications. Nurse Clin North Am. 2006 41: 487-98. 3- Orlowski JP, Cramer CL, Fiallos MR. Diabetic ketoacidosis in the pediatric ICU. Pediatr Clin North Am. 2008 55: 577-87. 4- Razavi Z. Frequency of ketoacidosis in newly diagnosed type 1 diabetic children. Oman Med J. 2010 25: 114-17. 5- Agus MS, Wolfsdorf JI. Diabetic ketoacidosis in the pediatric ICU. Pediatr Clin North Am. 2005 52: 1147-63. 6- Lone SW, Siddiqui EU, Muhammed F, Atta I, Ibrahim MN, Raza J. Frequency, clinical characteristics and outcome of diabetic ketoacidosis in chidren with type-1 diabetes at a tertiary care hospital. JPMA. 2010 60: 725-9. 7- Rewers A, Chase HP, Mackenzie T, et al. Predictors of acute complications in children with type 1 diabetes. JAMA. 2002 287: 2511-8. 8- Sheikholeslami H, Ziaee A, Shariatmadari M, Evaluation of clinical manifestation, laboratory data and precipitating factors in patients with diabetic ketoacidosis in educational and medical care center of Booali Sina in Ghazvin (1999-2004). J Birjand Unive Med Sci. 2008: 60-64. 9- Jayashree M,Singhi S. Diabetic ketoacidosis: predictors of outcome in a pediatric intensive care unit of a developing country. Pdiatr Crit Care Med. 2004 5: 492-3. 10- Marcin JP, Glaser N, Barnett P, McCaslin I, Nelson D, Trainor J. Factors associated with adverse outcomes in children with diabetic ketoacidosis-related cerebral edema. Pediatr. 2002 141: 793-7. 11- Jahagirdar RR, Khadilkar RR, Khadilkar AV, Lalwani SK. Management of diabetic ketoacidosis in PICU. Indian J Pediatr. 2007 74: 551-4. 12- Lawrence SE. Population-based study of incidence and risk factors for cerebral edema in pediatric diabetic ketoacidosis. J Pediatr. 2005 146: 688-92. 13- Edge JA, Hawkins MM, Winter DL, Dunger DB. The risk and outcome of cerebral oedema developing during diabetic ketoacidosis. Arch Dis Cild. 2001 85: 16-22. 14- Yordam N, Gönç EN, Kandemir N, Alikaşifoğlu A, Ozön A. Ten-year experience in management of diabetic ketoacidosis and ketosis: 140 episodes at pediatric age. Turk J Pediatr. 2005 47: 334-8. 15- Lin SF, Lin JD, Huang YY. Diabetic ketoacidosis: comparisons of patient characteristics, clinical presentations and outcomes today and 20 years ago. Chang Gung Med J. 2005 28: 24-30. 16- Flood RG, Chiang VW. Rate and prediction of infection in children with diabetic ketoacidosis. Am J Emerg Med. 2001 19: 270-3. 17- Ganesh R, Arvindkumar R, Vasanthi T. Clinical profile and outcome of diabetic ketoacidosis in children. Natl Med J India. 2009 22: 18-9. 18- Shiva S, Zarintan A. Clinical laboratory and epidemiological characteristics of diabetic ketoacidotic patients in children in Tabriz. J Tabriz Unive Med Sci. 2010 32: 53-57. 19- Irigoyen M, Cuartero B, Castellanos R, et al. Ketoacidosis at onset of type 1 diabetes mellitus in pediatric age in Spain and review of the literature. Pediatr Endocrinol Rev. 2012 9: 669-71. 20- Onyiriuka AN, Ifebi E . Ketoacidosis at diagnosis of type 1 diabetes in children and adolescents: frequency and clinical characteristics. J Diabetes Metab Disord. 2013 12: 47 doi: 10. 1186/2251-6581-12-47. 21- Abdul-Rasoul M, Al-Mahdi M, Al-Qattan H, et al. Ketoacidosis at presentation of type 1 diabetes in children in Kuwait: frequency and clinical characteristic. Pediatric Diabetes. 2010 11: 351-56.