Most ingested fish bones pass through the gastrointestinal tract without major complications. Migration of an ingested sharp fish bone from the site of entry into the surrounding soft tissue is a rare complication. Inflammatory diseases of the omentum are usually caused by intra-abdominal conditions, such as colon diverticulitis, omental torsion and infarction, and bowel perforation. We report a 63-year-old woman who suffered from intermittent dull abdominal pain over the left lower quadrant for about 2 months. Abdominal computed tomography revealed an omental inflammatory mass with a foreign body. An omental inflammatory mass with abscess was noted during laparotomy, and was excised totally. No gastrointestinal tract perforation was noted. Pathology examination confirmed a fish bone in the omental inflammatory mass. The post-operative course was uneventful. The patient was discharged on the 6(superscript th) day after the operation.