Background: Clinical presentation varies in children with Orthostatic Intolerance. This study aimed to evaluate the epidemiological and clinical characteristics of pediatric patients with orthostatic intolerance (OI) and positive head-up tilt test (HUTT). Methods: This study was a retrospective review of clinical data from outpatients over 18 months period. Results: We included 112 patients with abnormal HUTT results. Females were 78 (70%). Mean age of presentation was 15.6 years (sd: 3.3). Fifteen percent were overweight, and 14% were obese. A headache and syncope were the most frequent presenting symptoms (46% and 29% respectively). Review of systems identified more patients with headaches (84%), Syncope (61%), presyncope (87%) and abdominal pain (29%). Except for fatigue being more prevalent during a review of systems among patients with severe OI (69%) compared to those with moderate OI (46%, p Z 0.02), there was no statistically significant difference in the clinical Abbreviations: HUTT, head-up tilt table test; PC-presenting complaints, ROS-review of systems; OI-orthostatic intolerance, ANS-autonomic nervous system.