The gallstone ileus is a serious complication of cholelithiasis due to the formation of a fistula from the gallbladder to the subjacent duodenum. The gallstones are usually large enough to cause intestinal obstruction. The distal ileum, close to the ileocecal valve, is the most common site of obstruction in these cases, where the luminal diameter is narrowed. This condition is currently responsible for 4% of all the cases of mechanical bowel obstruction. However, when considering a 65+ age group, the rate goes up to 25%. In conclusion, gallstone ileus is a surgical emergency that, although rare, has high morbimortality rates. We present the case of a patient with an acute abdomen who did not respond to verbal stimuli, with a previous history of gallstone cholecystitis and significant weight loss. The diagnosis was based on anamnesis, physical examination and complementary exams, particularly in imaging exams. Exploratory laparotomy was performed with enterotomy, the removal of the gallstones and enterorrhaphy, without manipulation of the gallbladder or cholecystoduodenal fistula. The postoperative evolution was satisfactory without complications. The patient received hospital discharge in good clinical conditions, with the recommendation to stay in outpatient follow-up.