The maintenance of self-renewing stem cells, particularly hematopoietic stem cells (HSCs), relies on a balance between self-renewal and differentiation. This balance is regulated by various metabolic pathways, including anaerobic glycolysis, bioenergetic signaling, the AKT–mTOR pathway, glutamine (Gln) metabolism, and fatty acid metabolism. Hypoxia, a common feature of stem cell niches, promotes HSC maintenance by inducing anaerobic glycolysis and upregulating hypoxia-inducible factor 1α (HIF1α). HIF1α regulates glycolytic genes and blocks mitochondrial respiration to maintain quiescence. Other metabolic pathways, such as the PPP and FAO, also play crucial roles in stem cell homeostasis. The PI3K–AKT–mTOR pathway is activated by nutrients and growth factors, while the LKB1–AMPK pathway acts as a negative regulator of mTOR signaling. Gln metabolism supports energy production and oxidative stress response, and FAO provides NADPH to counteract oxidative stress. The precise mechanisms by which these metabolic pathways regulate stem cell fate decisions remain to be fully elucidated, but they hold significant therapeutic potential for tissue regeneration, aging, and degenerative disorders.The maintenance of self-renewing stem cells, particularly hematopoietic stem cells (HSCs), relies on a balance between self-renewal and differentiation. This balance is regulated by various metabolic pathways, including anaerobic glycolysis, bioenergetic signaling, the AKT–mTOR pathway, glutamine (Gln) metabolism, and fatty acid metabolism. Hypoxia, a common feature of stem cell niches, promotes HSC maintenance by inducing anaerobic glycolysis and upregulating hypoxia-inducible factor 1α (HIF1α). HIF1α regulates glycolytic genes and blocks mitochondrial respiration to maintain quiescence. Other metabolic pathways, such as the PPP and FAO, also play crucial roles in stem cell homeostasis. The PI3K–AKT–mTOR pathway is activated by nutrients and growth factors, while the LKB1–AMPK pathway acts as a negative regulator of mTOR signaling. Gln metabolism supports energy production and oxidative stress response, and FAO provides NADPH to counteract oxidative stress. The precise mechanisms by which these metabolic pathways regulate stem cell fate decisions remain to be fully elucidated, but they hold significant therapeutic potential for tissue regeneration, aging, and degenerative disorders.