Hookworm infection is one of the causes of long-term chronic hemorrhagic anemia in patients. This article reports a case of chronic severe anemia caused by hookworm infection.The capsule endoscopy showed that there were a large number of hookworms in the small intestine of a patient. At the same time, using the technique of saturated brine floatation and the automatic stool analyzer, hookworm eggs were detected.The patient's anemia was caused by hookworm infection and was significantly improved after anti-hookworm treatment.Hookworm infection cannot be ignored in the differential diagnosis of patients with chronic anemia. Capsule endoscopy combined with stool detection haves an important clinical value for the diagnosis of hookworm disease.© 2022. The Author(s) under exclusive licence to Witold Stefański Institute of Parasitology, Polish Academy of Sciences.