Background: Crohn's disease (CD) is one of two types of inflammatory bowel disease (IBD), a condition characterised by gastrointestinal tract inflammation that has become more common recently. For patients with IBD, nutrition plays a critical role in maintaining intestinal inflammation as the disease worsens. Methods: This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews standards. Three databases were used for the research: PubMed, Medline, and Google Scholar. As a result, 5 randomised controlled trials (RCTs) were identified for review. Results: After the review of the 5 RCTs regarding the use of omega-3 fatty acid intervention in patients with CD, especially focusing on the primary outcome, which was maintaining remission, the results from the 5 studies were somewhat contradictory. Nevertheless, overall, the intervention tended to have no significant effect on remission and could have other negative side effects on patients. Conclusion: This review suggests that the use of omega-3 supplementation as an intervention for patients with CD is not very promising. More research is needed to confirm its usefulness as a long-term intervention for patients with CD, with caution to side effects.