Hematopoietic stem cells (HSCs) are responsible for the production of blood cells throughout the human life span. Single HSCs can give rise to at least eight distinct blood cell lineages. Together, hematopoiesis, erythropoiesis and angiogenesis coordinate several biological processes, such as cellular interactions in development and proliferation, guided migration, lineage programming and reprogramming by transcription factors. Any dysregulation of these processes may result in hematological disorders and/or malignancies. Several studies of the molecular mechanisms governing HSC maintenance have demonstrated that protein regulation by the ubiquitin proteasomal pathway is crucial for normal HSC function. Recent studies have shown that the reversal of ubiquitination by deubiquitinating enzymes (DUBs) plays an equally important role in hematopoiesis; however, there is only limited additional information regarding the biological function of DUBs. In this review, we focus on recent discoveries that have led to a better understanding of the physiological roles of DUBs in hematopoiesis, erythropoiesis and angiogenesis. In addition, we discuss the DUBs associated with common hematological disorders and malignancies, which may potentially be therapeutic drug targets.