The incidence of lipoblastoma is low, with fetal occurrences being even rarer. There are very few prenatal reports about lipoblastoma. We present a case report of fetal perineal lipoblastoma, which was confirmed by pathology after birth. In this case, the combination of three-dimensional(3D) ultrasound greatly improved the diagnostic accuracy by determining the location and shape of the mass. Combining 3D ultrasound imaging with specific ultrasound characteristics related to different masses significantly enhances diagnostic accuracy for lipoblastomas during prenatal examinations. This case report provides valuable insights for prenatal diagnosis and counseling of lipoblastoma.