Adenovirus is a frequent cause of mild self-limiting upper respiratory tract infection, gastroenteritis, and conjunctivitis in infants and young children. Fatal infections (severe pneumonia progressing to respiratory failure, septic shock and/or encephalitis) are rare among immunocompetent adults. We report a case of severe adenovirus pneumonia in a young immunocompetent male who presented with sudden onset respiratory distress that progressed rapidly to respiratory failure and made a successful recovery on supportive measures. Systematic review of the literature identified 14 cases of severe adenovirus pneumonia (defined as respiratory failure requiring ventilatory support at any point during the course of illness) in otherwise healthy immunocompetent adults both in epidemic and community settings. We describe the clinical characteristics, radiological features, and outcome of identified cases.