Epigenetic therapy with hypomethylating agent (5-azacytidine; AZA) is common in the management of specific subtypes of myelodysplastic syndrome (MDS), but there are only few studies in chronic myelomonocytic leukemia (CMML) patients. In this paper our experience with 3 CMML patients treated with AZA is described. In one patient transfusion independency was observed after 4 treatment cycles; in one case a partial response was recorded, but a progression to acute myeloid leukemia (AML) after 13 AZA cycles has appeared. In one patient, AZA in reduced dosage was administered as a bridging treatment before allogeneic stem cell transplantation (ASCT), but in the control bone marrow aspirate (before ASCT) a progression to AML was recorded. Future studies are mandatory for evaluation of new molecular and clinical features which could predict the efficiency of hypomethylating agents in CMML therapy with respect to overall survival, event-free survival, quality-adjusted life year, and pharmacoeconomy.