Fibroblast growth factors (FGFs) belong to a family of pleiotropic heparin-binding growth factors. They exert multiple functions on various cell types of mesodermal and neuroectodermal origin, affecting cell proliferation, motility, survival, and differentiation. FGF's exert their activity by interacting with tyrosine kinase receptors (FGFRs) and cell-surface heparan sulfate proteoglycans. This article reviews recent studies on the role of the FGF/FGFR system in embryonic hematopoietic development, hematopoiesis, and hematological tumors. FGFs exert both autocrine and paracrine functions in these biological processes by acting on blood cells and their precursors and accessory cells in the bone marrow, including stromal and endothelial cells.