Acute mitochondriopathy and encephalopathy syndrome (AMES) is described differently by different authors in the literature. As a new clinical entity, we aimed to present the clinical signs and symptoms, diagnosis and treatment algorithm of our patients with AMES. 56 patients aged between 2 months and 18 years who were followed up in pediatric intensive care units of Konya Training and Research Hospital and Selcuk University Medical Faculty Hospital, between January 2010 and June 2017 were included. Patients’ data were obtained retrospectively from the intensive care unit patient files. 34 (60.7%) of the patients were male and 22 (39.3%) were female. The median age of our patients was 10.0 months. At the time of admission, 42 (75%) of the patients had fever, 35 (62.5%) vomiting, 27 (48.2%) abnormal behaviour and agitation and 28 (50%) convulsion. The etiological classification of patients with AMES was divided into four groups as infection, metabolic disorder, toxic, and hypoxic-ischemic. 39 (69.6%) patients were found to have infection, 10 (17.9%) patients hypoxia, 7 (12.5%) patients metabolic disorders. AMES occurs rarely, but should be kept in mind in the differential diagnosis of patients with any encephalopathy of unknown origin especially in those with a history of ingestion of drugs, previous viral infection and vomiting. Early recognition and treatment is imperative to reduce morbidity and mortality in children with AMES.