Background <p>Gingival diseases in Pakistan rank among the nation’s foremost oral health issues. Vitamins C and D may influence gingival health through collagen metabolism and immune regulation.</p> Objective <p>The study aimed to assess whether vitamin C and D supplementation can reduce bleeding on probing (BOP), measured as the percentage of bleeding sites (BOP%).</p> Materials and methods <p>A total of 136 school-going children, aged 8–16 years old, were included in this randomized controlled trial (RCT). Eligible participants presenting to the University of Lahore Dental Hospital were recruited. Oral health status was determined using the BOP examination. Participants were divided into two groups: Group A (standard care) and Group B (standard care plus vitamin C and D supplements). Children in both groups A and B were treated with ultrasonic scaling and given structured oral hygiene instructions. Children in group B (intervention group) were given an 8-week plan of vitamin C and D supplementation. Participants were recalled at 4 and 8 weeks to reassess.</p> Results <p>Among 150 enrolled children, 14 were lost to follow-up; 136 were included in analysis (Group A <i>n</i> = 68, Group B <i>n</i> = 68). Baseline BOP% was significantly higher in Group B (<i>p</i> &lt; 0.001). Thus follow-up comparisons were adjusted for baseline. Group B had lower BOP% than Group A at 4 weeks (<i>p</i> &lt; 0.001) and remained lower at 8 weeks (<i>p</i> &lt; 0.001). Both groups demonstrated a significant reduction in BOP% over time.</p> Conclusion <p>Vitamin C and D supplementation improved gingival health among school-going children.</p>