Angiosarcomas of the pleura are very rare tumors and it is difficult to differentiate them from other common pleural tumors such as mesothelioma and metastasic carcinoma clinically and pathologically. We report a case of a young Korean woman with angiosarcoma arising in the pleura. A 34-yr-old woman presented with dyspnea and chest tightness and pain for several months. A computed tomographic scan of the chest showed diffuse thickening of the left pleura and effusion with passive atelectasis. At thoracotomy the left pleura was thick and indurated. Histologically, the decorticated pleura revealed infiltration of sheets or cords of polygonal and epithelioid tumor cells showing rudimentary vascular differentiation. Immunohistochemically, the tumor cells were strongly positive for CD31, CD34, and vimentin, whereas weakly positive for factor VIII, and negative for cytokeratin, which are characteristic and specific findings of angiosarcoma.