Cardiorenal anemia syndrome describes the complex interaction between chronic heart failure, chronic kidney disease, and anemia, which often coexist and act synergistically. Anemia, highly prevalent among patients with heart failure and chronic kidney disease, arises primarily from iron deficiency, reduced erythropoietin synthesis, resistance to erythropoietin action, and systemic inflammation. The diagnosis of anemia and iron deficiency in cardiorenal anemia syndrome remains challenging due to the effect of systemic inflammation on several iron indices, such as ferritin and transferrin saturation, while both anemia and iron deficiency are independent prognostic factors for hospitalization, cardiovascular events, and all-cause mortality. Due to the lack of specific guidelines for the management of anemia in cardiorenal anemia syndrome, the therapeutic decisions are largely based on heart failure and chronic kidney disease guidelines. Current evidence supports the use of intravenous iron supplementation to improve functional status and quality of life, while the use of erythropoiesis-stimulating agents remains controversial. Moreover, emerging therapies, including hypoxia-inducible factor prolyl hydroxylase inhibitors and sodium-glucose co-transporter 2 inhibitors, might be promising in modulating erythropoiesis and iron homeostasis in this multifactorial syndrome. This chapter focuses on pathogenesis, diagnostic approach and current treatment strategies of anemia in patients with cardiorenal syndrome.