We are presenting the case of a 44–year old patient with large, well–differentiated liposarcoma of the right thigh. We are discussing the clinical findings, diagnosis and surgical treatment. The large dimensions (27/25 cm) and the origin of the tumor in popliteal fossa, migrating through the adductor canal (Hunter’s canal) in the anterolateral muscular space of the right thigh, represent the particularity of this case.