Thirteen patients (pts) with highly refractory acute myeloid leukemia (AML) 10 pts with de novo AML and 3 with blast crisis of chronic myeloid leukemia were treated with carboplatin (CP) 150 mg/m2/day through continuous IV infusion for 7 consecutive days. Seven of them received CP at least as third or more line therapy after a median duration of the disease of 26 weeks. None achieved a complete remission but a good hematologic response, with disappearance of circulating blast cells along with correction of bone marrow failure, persisting for 3 months was obtained in one patient and correction of hyperbasophilemia was observed in another with blast crisis of chronic myelogenous. Myelosuppression was the most consistent toxic effect. Two deaths occurred, one from renal acute failure and the other from sepsis. Median survival after CP was 8 weeks (range 4 days-11 months) and the majority of patients were able to return home. When used as a single agent and with the dose-schedule used in this study, CP does not appear effective in refractory AML. Other studies are necessary to assess its role at an higher dose or in combination with other agents in earlier phases of the disease.