Canine Erythropoietin (EPO) is a glycoprotein hormone belonging to the type I cytokine family that regulates erythropoiesis, the production of red blood cells. In dogs (Canis lupus familiaris), erythropoietin is produced primarily by peritubular interstitial cells of the kidney, with smaller amounts produced in the liver, in response to hypoxia or decreased oxygen-carrying capacity of the blood. Canine EPO binds to the erythropoietin receptor (EPOR) on erythroid progenitor cells in the bone marrow, activating intracellular signaling pathways such as JAK2–STAT5, PI3K–AKT, and MAPK, which promote the survival, proliferation, and differentiation of erythroid precursor cells into mature red blood cells. In canine health, erythropoietin is essential for maintaining normal hematocrit levels and adequate oxygen delivery to tissues, and insufficient EPO production is a major contributor to anemia associated with chronic kidney disease (CKD) in dogs. Dogs are also used as comparative animal models for renal anemia, and studies of canine erythropoietin have helped improve understanding of the pathophysiology of anemia of chronic kidney disease and the therapeutic use of recombinant erythropoietin or erythropoiesis-stimulating agents, benefiting both veterinary medicine and human nephrology.