Six patients with unresectable malignant mesothelioma were treated with chemotherapy consisting of doxorubicin and cisplatin every 3 weeks. One patient with paratesticular mesothelioma metastatic to lungs entered complete remission for 8 months; his disease has relapsed but he is alive 32 months after initiation of chemotherapy. One patient with peritoneal mesothelioma achieved partial response for 12 months. Two patients with pleural mesothelioma achieved a partial response of 5- and 6-month durations, respectively. Two patients with pleural mesothelioma failed to respond to this regimen. Thus, four of six patients responded to doxorubicin-cisplatin chemotherapy. These preliminary results merit further study and confirmation; future investigations of cisplatin alone are necessary to better define the role of this agent in mesothelioma.