Lipoma is a rare benign neoplasm of mature fat cells. Asymptomatic abdominal mass, progressive abdominal distension, and intraperitoneal radiolucent fat density mass on computed tomography are the main clinical symptoms and signs. An unusual case is presented in this report. A complete excision was performed on an 11-month-old boy with a giant omental lipoma, and no recurrence was found in the 12-month follow-up.