Vitamin A deficiency (VAD) after bariatric surgery is a well-documented complication. Clinical signs of VAD deficiency are significant if the vitamin A level is below 100 μg/L (4 μmol/L). Main symptom of VAD is nyctalopia. It has been described in several reports after malabsorptive bariatric procedures. We report a 52-year-old man with VAD complained of night blindness and optic neuropathy after undergoing a duodenal switch procedure. The case illustrates the necessity of lifelong vitamin supplementation after malabsorptive bariatric operations.