Hookworm is one of the most common nematode causing intestinal infestation in the world. Patients with a mild hookworm load are usually asymptomatic, but a moderate or heavy hookworm burden can result in fatigue, recurrent abdominal pain and iron-deficiency anemia. We present here an unusual case of a 35-year-old man with iron deficiency anemia in whom adult hookworm were visualized and recovered on gastroscopy. There was no eosinophilia, and stool examination was negative for occult blood, and parasite ova/cysts. Upper gastroscopy revealed several squirming red worms in the stomach. Ancylostoma duodenale infection was confirmed by histopathological examination and eradicated by albendazole successfully. His anemia was corrected after treatment.