b＞Introduction/b＞ Avoidant/restrictive food intake disorder (ARFID) is an eating or feeding disturbance manifested with persistent failure to meet appropriate nutritional or energy needs. Since first defined in DSM-5 in 2013, ARFID is still not well known. The goal of this study is to identify the characteristics of ARFID from a pediatric point of view. b＞Methods/b＞ Among the patients with eating disorders aged 8-18 who were hospitalized from Jan, 2013 to May, 2021 at the Department of Pediatrics at SNUCH, we selected the patients diagnosed with ARFID after collaboration with the Department of Psychiatry. Clinical characteristics such as age, sex, anthropometry, biochemical abnormalities, clinical outcomes, et al. were evaluated. b＞Results/b＞ A total of 17 patients were finally diagnosed with ARFID. Among them, the initial diagnosis of 12 patients were not ARFID, most common initial diagnosis was anorexia nervosa (n=6). The onset age was 11.8±2.6 years old and 5 (29.4%) were male. Loss of appetite (47.1%) was the most common initial symptom. It took 7.0±5.2 months from symptom onset to hospitalization, and hospitalization period was 11.2±12.9 days. Weight change was 11.2±5.9 kg, and at the lowest body weight, BMI was 13.8±1.7, and z-score of BMI was -2.8±1.0. Based on BMI, 7 patients (41.2%) were moderate acute malnutrition and 6 patients (35.3%) were severe acute malnutrition. Blood tests showed various abnormal findings such as vitamin D deficiency (80%), dyslipidemia (41.7%), anemia (35.3%) et al. Other tests revealed abnormal findings such as sinus bradycardia (58.3%), pleural effusion (25%), reflux esophagitis (18.8%), et al. 6 patients (35.3%) received intravenous nutrition and 2 patients (11.8%) received tube feeding. Refeeding syndrome occurred in 4 patients (23.5%). 1 patient needed in-patient care to the pediatric psychiatric ward. b＞Discussion/b＞ This is the first study of ARFID among children and adolescents in Korea. Accurate diagnosis of ARFID is essential, even though there are many overlapping symptoms with anorexia nervosa, and differential diagnosis between them is essential. Collaboration between Pediatrics and Psychiatry is important, because excluding organic abnormalities, proper nutritional assessment and integrative treatment are crucial to clinical outcome of ARFID.