Objective: Severe anaemia is reported to occur in severe hookworm infection in many studies. But so far detailed study of the role of percent transferrin saturation, serum iron and total iron binding capacity which indicate iron-deficient erythropoiesis and iron status in patients with severe anaemia due to hookworm infection diagnosed by doing upper gastro intestinal endoscopy was not done. Hence a detailed study of the role of percent transferrin saturation, serum iron and total iron binding capacity which indicate iron-deficient erythropoiesis and iron status in patients with severe anaemia due to hookworm infection diagnosed by doing upper gastro intestinal endoscopy was done in our institute. Methods: A study of 1259 patients who had undergone upper gastro-intestinal endoscopy for a period of 5 years from May 2009 to April 2014 was carried out in our institute. In each of these 1259 patients, the first and second part of duodenum were carefully examined to find out the presence of hookworms. In all the patients found to have hookworms in duodenum,investigations were done to know about the presence of anaemia except in the very few patients who were lost for follow up. In patients with severe anaemia [haemoglobin __ampersandsignlt;7g/dl or g%] peripheral smear examination was also done in addition to haemoglobin estimation . But in one patient with severe anaemia various investigations which indicate iron-deficient erythropoiesis and iron status were also done namely transferrin saturation, serum iron and total iron binding capacity[TIBC] in addition to haemoglobin estimation and peripheral smear examination . The results were found as given below. Results: Of these 1259 patients, as many as 18 patients were found to have hookworms in duodenum while doing upper gastrointestinal endoscopy. Of these 18 patients, 4 patients were lost for follow up and full details about their investigations were not available. The remaining 14 patients were taken into consideration for our study. Of these14 patients, 9 patients had anaemia and 2 of these 9 patients were found to have severe anaemia [haemoglobin 3.2g%, haemoglobin 2.1 g%.] The peripheral smear of both the patients showed severe hypochromic anaemia. In one patient with severe anaemia [haemoglobin 3.2g%] in whom various investigations which indicate iron-deficient erythropoiesis and iron status were also done, transferrin saturation and serum iron were extremely low but total iron binding capacity[TIBC] was normal. Conclusion: Hence measurement of transferrin saturation, serum iron and total iron binding capacity could reveal iron-deficient erythropoiesis and deteriorating iron status in patients with severe anaemia due to hookworm infection.