Abstract: Dietary therapy represents a promising approach to modulate gut microbiota in patients with inflammatory bowel disease (IBD) and may ameliorate certain neurological conditions through the gut-brain axis. The dietary therapy rich in fatty acids has been demonstrated therapeutic efficacy in both IBD and central nervous system (CNS) disorders, mainly manifested as controlling intestinal and neural inflammation through fatty acids. However, robust clinical evidence regarding the efficacy of dietary therapy against neurological manifestations in IBD remains limited. Therefore, this review summarizes the effects of fatty acid-rich dietary therapy in patients with IBD or CNS disorders, as well as the underlying mechanisms of fatty acids, with the aim of providing a reference for the application of such dietary therapy in IBD patients presenting with concurrent CNS manifestations and the development of treatment protocols.