The idiopathic omental infarction (IOI) is a rare cause of acute abdomen. It is usually a self-limited disorder presenting with nonspecific abdominal pain that may mimic several acute abdominal conditions, such as appendicitis, cholecystitis, diverticulitis, epiploic appendagitis, and mesenteric panniculitis. In the present era, more cases of IOI are being diagnosed preoperatively by computed tomography (CT scan).If the diagnosis was made in the initial period of patient’s visit, the conservative treatment is feasible and surgery can be avoided. Surgical treatment is indicated only in cases of secondary infection. Here we report a case of 28-year-old obese male (height :177.5 cm, body weight: 96 Kg, BMI 30.5kg/m2) who represented with pain at right upper quadrant of abdomen for 3 days and it got worse upon movement of body or sitting up from the bed. Initial lab data were normal, no significant findings in abdominal ultrasound except severe fatty liver, but abdominal CT revealed omental infarction at right upper quadrant. He was discharged uneventfully after 6 days of hospitalization after conservative management with pain control and empiric antibiotics. The aim of this report is to emphasize the importance of a differential diagnosis of the acute abdomen and to discuss the management of omental infarction. In this report, we present a review of current literature on omental infarction and highlight the importance of imaging study especially abdominal CT scan in the nonoperative diagnosis and conservative management.