〔Abstract〕 Objective To clarify the intrinsic link between a high-fat diet(HFD) and the pathological progression and prognosis of spinal cord injury(SCI) while preliminarily exploring the potential underlying mechanisms. Methods SCI models were established in mice that were fed either a regular diet(RD) or HFD, with injury inflicted specifically on the T9-T12segments. Hematoxylin-Eosin(HE) staining, Masson staining, and Nissl staining were used to observe the local histological changes in SCI tissues. The basso, beattie, and bresnahan(BBB) score and footprint analysis were used to evaluate and compare hindlimb functional recovery after SCI in both RD and HFD mice.In vitroexperiments were conducted to identify key fatty acids in the HFD that exacerbate neuronal damage, whilein vivoexperiments assessed the effects of 2-bromopalmitate(2-BP), a palmitic acid inhibitor, on HFD-fed mice with SCI. Results Compared to RD-fed mice, HFD-fed mice exhibited significantly larger lesion areas, more severe neuronal damage, and poorer hindlimb functional recovery after SCI. Palmitic acid was identified as the key fatty acid aggravating neuronal damage. Further more, inhibition of palmitoylation, mediated by palmitic acid, enhanced neuronal survival, promoted tissue repair, and improved hindlimb functional recovery in HFD-fed mice post-SCI. Conclusion HFD exacerbates pathological damage following SCI in mice through palmitic acid, impairing recovery. Palmitic acid-mediated palmitoylation is likely the main mechanism underlying this effect.