Aim: To assess the correlation of Sodium Valproate on serum Vitamin D3 levels in ambulated epileptic children on sodium valproate monotherapy. Material & Method: Study was conducted from January 2020 to Dec 2021 at a tertiary care centre in North India. Ambulatory children with epilepsy aged one to 18 years receiving Sodium Valproate monotherapy for more than six months are included. Children on valproate were cases and healthy children as controls. Children on more than one drug and those who didnot consent were excluded. Result: 130 children were included in the present study. Vitamin D levels were significantly lower in children on valproate therapy compared to the controls. Mean levels in cases and controls were 14.98+ 2.19 ng/ml cf. 25.90+ 3.14ng/ml respectively (p<0.001).Additionally, there was a strong negative correlation of serum valproate and vitamin D levels. (Pearson’s correlation value of < .0001).A strong negative correlation of duration of AED and vitamin Dlevels among the cases was also observed (Pearson’s correlation value of < .0001). Further, it was noted that after vitamin D3 supplements of 60000 IU weekly for six weeks, 10% children did not achieve levels of 20 ng/ml (defined at the cut off for deficiency). The study concluded that all children on valproic acid medication be given vitamin D supplementation, regularly monitored with vitamin D3 levels in blood. Vitamin D3 levels should be reviewedafter supplementation as not all children may become sufficient. Conclusion: There is a significant risk of vitamin D deficiency in ambulant children with drug treated epilepsy. Blood vitamin D levels should be monitored on a regular basis throughout anticonvulsant therapy.