Background: Inflammatory bowel diseases (IBD) are a heterogeneous group of chronic relapsing diseases of the gastrointestinal tract. Intestinal fatty acid- binding proteins (I-FABP) defined as circulating or urinary markers of intestinal epithelial damage in patients with acute ischemia of the small bowel. Aim and objectives: to evaluate I-FABP level in the follow up of treated IBD patients compared to healthy control subjects. Subjects and methods: A case control study which included 60 patients was diagnosed IBD divided into equal two groups according to conventional or biological treatment and 30 healthy control subjects, aged from 16-70 years old. All investigations done accordingly plus I-FABP by Eliza. Results: In IBD females were 53% in conventional group. Laboratory findings were of statistical significant as regard higher Hb and lower number of platelets in biological group compared with conventional group, p value was .024 &.006 respectively. FABP levels were significantly elevated in studied IBD cases compared to control group, p value was .000 common complaint was abdominal pain in conventional group (70% versus 43.3% in biological group), while diarrhea was the most common in biological group (50% versus 20% in conventional group). Colonic left sided lesions in both groups. Cut off value of plasma FABP was 4.65 for all IBD patients with an AUC 98%, 77% and 0.992 respectively. Conclusion: I-FABP proved to be a useful biological marker in the diagnosis of IBD and can be used to monitor the progress of IBD.