Before the introduction of upper gastro intestinal endoscope, the only way to diagnose hookworm infection is by doing stool examination for hookworm ova. But after the introduction of upper gastro intestinal endoscope there has been many reports of finding live adult hookworms in duodenum and rarely in stomach while doing endoscopy. Hence upper gastro intestinal endoscopy is an extremely useful investigation to demonstrate and diagnose the presence of live adult hookworms especially in patients with severe anaemia. One such adult hookworm retrieved out while doing endoscopy in a patient with severe anaemia in our institute was examined under light microscope and was identified as female Ancylostoma duodenale. Various light microscopic images and features of this hookworm and the scientific facts by which the hookworm was identified as female Ancylostoma duodenale are described below in detail as such reports are extremely rare in the literature.