Background: Small bowel diverticula are a rare condition occurring mainly in the elderly. They can be isolated or multiple and can involve the duodenum, jejunum and ileum. Acute complications are extremely rare, with an aspecific pattern of symptoms. The aim of the study is to report the different patterns of presentation of patients with complicated jejunoileal diverticula. Methods: This is a retrospective descriptive study on a consecutive series of patients admitted for complicated jejunoileal diverticula in four Italian surgical departments between 2012 and 2019. Complications included acute diverticulitis, bleeding, perforation and intestinal obstruction. Patients presenting with complicated duodenal or Meckel's diverticula were not included. Results: Twenty-six patients were enrolled. The median age was 77 (46–94) years. Abdominal pain, fever and nausea/vomiting were the most frequent symptoms at presentation. Abdominal computed tomography (CT) was diagnostic in 35% of patients. Ten (38%) patients had bowel perforation, nine (35%) acute diverticulitis, five (19%) bowel obstruction and two (8%) had intestinal bleeding. Twenty-one (81%) patients underwent surgery, two (8%) were managed by CT-guided drainage of collections and three (11%) were treated with antibiotics. One patient died post-operatively. The median hospital stay was 9 (5–62) days. Conclusion: Acutely complicated jejunoileal diverticula are infrequent, but a strong suspect should be raised whenever elderly patients are admitted for unspecific abdominal pain with a non-diagnostic CT scan. Conservative management may be offered in very selected cases if a diagnosis is obtained, but in most instances, surgery is both diagnostic and therapeutic.