Small extracellular vesicles (sEVs) transfer cargos between cells and participate in various physiological and pathological processes through their autocrine and paracrine effects. However, the pathological mechanisms employed by sEV-encapsulated microRNAs (miRNAs) in acute myeloid leukemia (AML) are still obscure. In this study, we aimed to investigate the effects of AML cells-derived sEVs (AML-sEVs) on AML cells and delineate the underlying mechanisms. We initially used high-throughput sequencing to identify miR-221-3p as the miRNA prominently enriched in AML-sEVs. Our findings revealed that miR-221-3p promoted AML cell proliferation and leukemogenesis by accelerating cell cycle entry and inhibiting apoptosis. Furthermore, Gbp2 was confirmed as a target gene of miR-221-3p by dual luciferase reporter assays and rescue experiments. Additionally, AML-sEVs impaired the clonogenicity, particularly the erythroid differentiation ability, of hematopoietic stem and progenitor cells. Taken together, our findings reveal how sEVs-delivered miRNAs contribute to AML pathogenesis, which can be exploited as a potential therapeutic target to attenuate AML progression.