Background: Multiple sclerosis (MS) is an autoimmune illness that can be triggered by both hereditary and environmental factors. There are crucial roles for the neuroendocrine system in initiating autoreactive immunity at this stage. Copeptin is a promising inflammatory marker that has the potential to be employed as a prognostic factor in several disorders, particularly those affecting the central nervous system. Objectives: In this research we attempt to evaluate the relation of serum copeptin concentrations with weight increment in Iraqi patients with multiple sclerosis. Methods: A cohort of Sixty Iraqi patients with multiple sclerosis took part in this study and classified equally into three groups; obese group, overweight group, and normal-weight group respectively. Serum lipid profile was estimated using Biosystem kit, while serum copeptin estimated using My BioSource ELISA kit. A statistical analysis was conducted using the IBM SPSS software package (version 27.0). Results: Serum copeptin levels were higher in obese as well as overweight MS patients compared to MS patients with normal weight (170.7, 160 vs. 149.3pg/ml) respectively. Also, it showed a significant positive correlation (P ⩽ 0.05) with BMI, serum TG and serum VLDL in overweight MS patients. Conclusion: Iraqi multiple sclerosis patients who have excess in body weight have higher levels of serum copeptin when compared to those MS patients with normal weight. The positive significant correlation of serum copeptin with BMI, serum TG, and serum LDL among overweight MS patients may indicate a pathogenic role of copeptin as a neuroendocrine in the adipose dysfunction and related diseases.