Gliosarcoma is a rare malignant, biphasic brain tumor composed of glioblastoma multiforme and sarcomatous components. Various types of sarcomatous differentiation are described in this tumor: fibrosarcomatous, malignant fibrous histiocytoma-like, chondrosarcomatous and osteosarcomatous types. We report an extremely unusual variant of liposarcomatous differentiation in gliosarcoma in 72-year-old woman. Fat cells were presented by atypical multivacuolar and monovacuolar lipoblasts, stained positive for S100. p53 that was positive in both glial and mesenchymal cells of the tumor were negative in the lipoblasts. To the best of our knowledge, this is the first report in the literature of liposarcomatous differentiation in gliosarcoma.