Background and purpose: Inflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) are both chronic gastrointestinal diseases with different pathophysiology but similar symptoms. In this study, we intend to investigate the pattern of changes in plasma levels of Fe, Zn, Se, Cu and ferritin, transferrin and ceruloplasmin, as well as oxidative and antioxidant capacity in IBD patients compared to IBS and the healthy group.Methods: This case-control study was performed on three groups of 30 patients with IBD and IBS and healthy individuals. ELISA method was used to measure the levels of ferritin and total oxidant, atomic absorption method for selenium and copper, and spectrophotometry for iron, zinc, transferrin and ceruloplasmin.Results: According to the results of this study, we showed that the levels of oxidative stress and transferrin, selenium, and zinc in men with IBD compared to IBS and control, showed a significant difference while in women no significant changes were observed in other factors except transferrin and Zn. There was also a significant increase in MDA, a decrease in TAC and a decrease in zinc and transferrin in the entire population with IBD. Also, lower levels of Fe and Se were observed in IBD patients compared to IBS and the healthy group. However, this difference was not statistically significant.Conclusion: The results of this study showed that the study of some trace elements may help us to find a more effective and easier method in diagnosing and differentiating people with IBD and IBS.