The authors present the data available in the literature and their observation of mesenchymal chondrosarcoma of the lung a 68-year-old female patient. Histologically, the tumor is exhibited by the fields of monomorphic round and oval cells with hyperchromic muclei and a scanty cytoplasm, with the hemangiopericytoma-like structures being formed here and there. There are foci of chondroid cells, portions of necrosis, and an ample quantity of mitoses. Immunohistochemical study has revealed that the tumor cells show the expression of vimentin, S-100 protein, neuron-specific enolase and the cytoplasmic expression of CD 99. The tests using CD 31, CD 34, factor VIII, desmin, total cytokeratin, or synaptophysin are negative.