Irritable bowel syndrome (IBS) is characterized by abdominal pain associated with changes in defecation frequency and blood folate level. FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides and polyols. High-FODMAP diet could elicit or exacerbate IBS-associated bowel symptoms, which is inadequately recognized among gastroenterologists in China. Here we report an IBS case, focusing on the association between high-FODMAP diet and bowel symptoms and the intervention of low-FODMAP diet.