This systematic review evaluates the hypothesis that optimal serum magnesium levels may enhance remission rates in Crohn's disease (CD) and considers whether magnesium supplementation could be beneficial in CD management. This review aims to synthesize available evidence concerning the impact of serum magnesium on disease remission in CD, and to analyze the effectiveness and mechanistic roles of magnesium supplementation. Adhering to the PRISMA guidelines, we searched PubMed, Web of Science, and Scopus up to January 2024 using MeSH terms and free-text queries related to CD and magnesium. The inclusion criteria were studies that investigated serum magnesium levels, effects of supplementation, and the inflammatory mechanisms in CD remission. From the 525 records identified, eight studies met the inclusion criteria after the removal of duplicates and irrelevant records. These studies, conducted between 1998 and 2023, involved a cumulative sample of 453 patients and 292 controls. Key findings include significantly lower serum magnesium levels in CD patients (0.79 ± 0.09 mmol/L) compared to controls (0.82 ± 0.06 mmol/L), with up to 50% prevalence of hypomagnesemia in CD patients observed in one study. Notably, CD patients, particularly men, exhibited lower magnesium intake (men: 276.4 mg/day; women: 198.2 mg/day). Additionally, low magnesium levels correlated with increased sleep latency (95% CI -0.65 to -0.102;