AIM: To determine the vitamin D levels in vernal keratoconjunctivitis (VKC) patients in Indian population. METHODS: A total of 30 non-atopic healthy children and 30 children having VKC were included in the study. The serum vitamin D levels and the time spent outside was compared between the two groups (P<0.05). RESULTS: The mean serum vitamin D level in the VKC group was significantly lower (mean 19.17±10.76 ng/mL) compared to the control group (mean 31.19±9.09 ng/mL) (P=0.0003). The vitamin D levels were found to be deficient (10-20 ng/mL) in 43.33%, whereas severe deficiency (<10 ng/mL) was found in 20% of the VKC patients. The deficiency of vitamin D correlated with the level of severity of VKC (P<0.02). The time spent outside in the VKC group was 1.07±0.76h, whereas in the healthy subjects it was 2.08±0.72h (P<0.0001), and it showed a significant correlation with the serum 25 (OH) D3 levels (r=0.478, P<0.001). CONCLUSION: The study shows that children with VKC had a significantly lower serum vitamin D levels as compared to the healthy children which correlated with time spent outside. The severity of VKC also correlated with the severity of vitamin D deficiency which suggests that vitamin D plays an important role in maintaining ocular surface health.