Background and Aim: Individuals with chronic liver disease (CLD) are highly vulnerable to vitamin D deficiency, which is associated with mortality and complications such as hepatic encephalopathy and hepatic osteodystrophy in liver cirrhosis. This research aimed to evaluate the association between vitamin D levels and illness progression in CLD individuals by comparing vitamin D concentrations in the normal population and CLD cases based on the Child-Pugh Classification (Classes A, B, and C). Methodology: A comparative cross-sectional study was conducted over a six-month period involving 148 participants: 73 healthy individuals and 75 CLD patients. The CLD patients were systematically divided into three groups of 25 patients each based on their Child-Pugh scores (A, B, and C). Statistical comparison of vitamin D levels employed the independent t-test (for normal vs. CLD groups and Hepatitis B vs. C groups), ANOVA (for Child-Pugh classes), and chi-square analysis (for gender correlation). Results: The study revealed that 33% of those with CLD were vitamin D deficient, contrasting with 19% of the general population. The Child-Pugh classification was significantly correlated with vitamin D levels ($p<0.05$). The results demonstrated that the majority of CLD patients, particularly those in Child-Pugh Class B and C, were vitamin D deficient. Low vitamin D concentrations were predicted by the female sex (60%). Although individuals with HBV and HCV infections exhibited low vitamin D levels, there was no strong evidence of a statistically significant difference in vitamin D concentrations between these two viral groups. Conclusion: CLD patients exhibit a greater prevalence of vitamin D deficiency, which is clearly associated with the female sex and increased CLD severity. It is recommended that chronic CLD patients, particularly those in Child-Pugh Classes B and C, undergo routine vitamin D testing and receive prompt supplementation to improve prognosis and management.