Palpable inguinal mass in children should be differentiated from inguinal hernia, hydrocele, lymph node, and tumor. Though using ultrasonography, fatty tumor would be misdiagnosed as incarcerated inguinal hernia containing fatty component. We experienced the huge inguinal lipoblastoma in 5-year-old girl mimicking recurrent incarcerated hernia. Laparoscopic exploration revealed it was not incarcerated hernia but well demarcated bulging mass from abdominal wall. Mass was about 10×4×3 cm and extended from internal inguinal ring to saphenous opening. It was near total excised because of right external iliac vein injury. Pathologically, it was proven as lipoblastoma containing mature adipocyte with lipoblast and fibrous septa. Postoperatively, we noticed a segmental thrombotic occlusion of external iliac vein. After 1 year, she has no symptom related to occluded vessel. The remained lipoblastoma showed no interval change. Even lipoblastoma has a good prognosis with low recurrence rate, we need careful follow-up.