Mesenteric lipoma is a rare benign tumor of mature fat cells. Asymptomatic abdominal mass, progressive abdominal distension, and intraperitoneal radiolucent fat density mass on computed tomography are the main diagnostic criteria. Main differential diagnosis is lipoblastoma or lipoblastomosis. Treatment is surgical excision. As an unusual case, a 3-year-old boy with a giant mesenteric lipoma is presented in this report.