A new exciting area in cancer research is the study of cancer stem cells (CSCs) and the translational implications for putative epigenetic therapies targeted against them. Accumulating evidence of the effects of epigenetic modulating agents has revealed their dramatic consequences on cellular reprogramming and, particularly, reversing cancer stemness characteristics, such as self-renewal and chemoresistance. Lysine specific demethylase 1 (LSD1/KDM1A) plays a well-established role in the normal hematopoietic and neuronal stem cells. Overexpression of LSD1 has been documented in a variety of cancers, where the enzyme is, usually, associated with the more aggressive types of the disease. Interestingly, recent studies have implicated LSD1 in the regulation of the pool of CSCs in different leukemias and solid tumors. However, the precise mechanisms that LSD1 uses to mediate its effects on cancer stemness are largely unknown. Herein, we review the literature on LSD1’s role in normal and cancer stem cells, highlighting the analogies of its mode of action in the two biological settings. Given its potential as a pharmacological target, we, also, discuss current advances in the design of novel therapeutic regimes in cancer that incorporate LSD1 inhibitors, as well as their future perspectives.