Many patients with hematologic malignancies show immunosuppression and/or neutropenia, and are at a high risk of developing a serious infection that would require empiric therapy with broad-spectrum antibiotics. However, a thorough comparison of the efficacies of different carbapenems has not been carried out. To compare the efficacies of meropenem (MEPM) and doripenem (DRPM) in febrile patients with hematologic neoplasms, we retrospectively reviewed data of 149 consecutive febrile patients with acute myeloid leukemia, acute lymphoblastic leukemia, or myelodysplastic syndrome (MDS) who were treated empirically with MEPM or DRPM. The duration from the start of carbapenem administration to decline of fever was not significantly different between the MEPM and DRPM groups (median, 3 versus 4 days; P = 0.79). Multivariate analysis showed that a diagnosis of MDS and the use of liposomal amphotericin-B or voriconazole are statistically significant risk factors for sustained fever. In conclusion, MEPM and DRPM showed similar efficacies in febrile patients with acute leukemia and MDS.