Background: Serum sodium levels have been recognized as a prognostic marker in chronic liver disease, particularly in decompensated cirrhosis. This study aimed to investigate the association between serum sodium levels and clinical outcomes in patients with chronic decompensated cirrhosis.Methods: A prospective observational study was conducted on 90 patients with chronic decompensated cirrhosis. Serum sodium levels were measured, and patients were categorized into four groups: <125 mEq/L, 125-129 mEq/L, 130-134 mEq/L, and ≥135 mEq/L. The relationship between serum sodium levels and various clinical parameters, complications, mortality, hospital stay, and ICU requirement was analyzed. Results: The majority of patients (57.8%) were in the age group of 40-59 years, and males constituted 82.2% of the study population. Serum sodium levels showed a significant inverse correlation with ChildPugh scores (r=-0.723, p<0.001) and MELD scores (r=-0.739, p<0.001). Patients with lower serum sodium levels had a significantly higher prevalence of complications, including hepatorenal syndrome (18.8% in patients with serum sodium <125 mEq/L), spontaneous bacterial peritonitis (12.5%), hepatic encephalopathy (68.8%), and coagulopathy (81.3%). Lower serum sodium levels were also associated with increased mortality, prolonged hospital stay, and higher ICU requirement (p<0.001). Conclusion: Serum sodium is a valuable prognostic marker in patients with chronic decompensated cirrhosis. Lower serum sodium levels are associated with more advanced liver disease, higher prevalence of complications, increased mortality, prolonged hospital stay, and higher ICU requirement. Incorporating serum sodium levels into the assessment and management of these patients can aid in risk stratification and treatment decisions