Background: Irritable bowel syndrome is a widespread digestive disorder that is characterized by diarrhea and/or constipation, bloating, and associated with abdominal pain. This disorder can seriously display individuals and quality of life. Aim: The aim was to evaluate the effect of an educational module on knowledge level, symptoms severity & quality of life in patients with irritable bowel syndrome. Method: Quasi-experimental research design (pre posttest and follow up) was applied.  Fifty adult IBS patients (Rome criteria) were prospectively enrolled in this study in out-patient clinic at south valley University Hospital. Demographic, clinical data and knowledge were recorded. Patient's quality of life subscales (dysphoria, interference with activity, body image, health worry, food avoidance, social reaction, sexual concerns, & relationships). and disease severity also were assessed. Results: The results revealed that total mean knowledge scores of patients' post-educational intervention were improved than that of their pre-scores, increase the mean scores of quality of life subscales post and follow-up educational intervention compared to pre educational intervention with highly statistically significant differences between them at p < 0.001.  Also, this study showed that 60.0% of the studied patients had moderate symptoms pre educational intervention compared with 36.0 % post and 42.0 % in follow-up phase with a highly significant difference between them (P< 0.01). Conclusion & Recommendations: The educational module is effective in enhancing knowledge, quality of life, and decreasing the symptoms severity in patients with irritable bowel syndrome. Continuous patient education must be planned regularly to control disease symptoms and improve quality of life.