Background: Irritable bowel syndrome (IBS) is a functional gastrointestinal syndrome with an expanding worldwide incidence. Low FODMAP diet is a recently developed dietary strategy consists of limiting foods that are high fermentable, which might induce or aggravate IBS symptoms.Aerobic exercise is beneficial in reducing the risk of all types of gastrointestinal symptoms. Objective: Investigate the effect of low FODMAP diet and aerobic exercise on irritable bowel syndrome post abdominal surgeries. Patients and methods: Forty five female and male patients participated in this study. They were divided into three equal groups, group (A) received low FODMAP diet group (B) received aerobic exercise (walking on treadmill 25-40 minutes 3 times per week) group (C) received both low FODMAP diet and aerobic exercise. Evaluation was done pre- and post- 12 weeks of treatment by IBS Severity Scoring System (IBS-SSS) and IBS Quality of Life (IBS-QOL). Results: There was significant reduction in post-treatment values of IBS-SSS and IBS-QOL in comparison to pre-treatment values in the three groups, Post-treatment comparison between three groups showed significant difference in IBS-SSS and IBS-QOL, which revealed a significant reduction in IBS-SSS and IBS- QOL of group C compared to that of group A and group B. Conclusion: combining low FODMAP diet and aerobic exercise had a greater effect on irritable bowel syndrome through reducing IBS symptoms and improving quality of life.