Primitive intrathoracic liposarcomas are rare tumors mostly located in the mediastinum or in lung parenchyma. Primitive liposarcomas of the pleura are exceptional and show a dramatic clinical course. These tumors are treated by surgery sometimes associated with radiotherapy. We report 2 cases of primitive liposarcoma of the pleura occurring in 2 women of 19 and 62 years of age. Histological examination showed in both cases a low-grade myxoid liposarcoma. In one case, ultrastructural study confirmed the diagnosis.