Purpose: Gingivitis is the inflammation of gingiva and a mildest form of periodontal disease. Earlier studies have revealed that vitamin D has an anti inflammatory effect on gingiva and low levels of serum vitamin D are associated with many chronic diseases.. The objective of this study was to assess the association of serum level of 25-OHD to marginal gingivitis. Materials and Methods: This was a cross sectional study conducted in Maratha Mandal dental college, Belgaum, India. Out of the 451 people screened, 96 subjects who had Gingivitis score more than 1 and who satisfied the inclusion criteria and signed the informed consent were considered for the study. The gingival status was assessed by Loe and Silness Index and the serum vitamin D levels of 25-OHD were analysed by The Diasorin vitamin D Direct Elisa kit Germany. Also the information on the Demographic profile which included the age, sex, weight and calculus status was collected in the form. Results: On statistical analysis the relationship of serum vitamin D with gingival status was found to be negative and statistically significant at P<0.05. Further with multivariate analysis the total contribution of age, sex, vitamin D, weight and calculus on gingival status was 38.92% in which the calculus status contributed maximum of 20.11% compared to minimum of 0.83% by gender, followed by serum vitamin D 11.77%, age by 3.96% and weight by 2.25% respectively. Conclusion: Based on this analysis we can conclude that serum vitamin D and calculus are the most important contributors for the gingival status.