Anemia has a high prevalence in patients with lung cancer. Its frequency and severity depend on tumor stage, duration of disease, and previous and current treatment. Anemia affects the health-related quality of life and impacts prognosis and outcome of therapy. Despite this clinical relevance, anemia is often underrecognized and undertreated. Treatment options include the administration of hematopoietic growth factors and red blood cell transfusions. Blood transfusions result in rapid but often transient improvement of anemia. Administration of epoetin or darbepoetin alfa increases hemoglobin levels, decreases blood transfusions, and improves quality of life in patients with lung cancer. Trials determining the exact association of anemia with response to chemotherapy/radiation therapy and survival are ongoing. Oncologists must be aware of the clinical relevance of anemia and offer adequate treatment options to their patients.