Epilepsy is one of the most serious neurological disorder. The purpose of present study was to determine serum prolidase enzyme activity in children taking anti-epileptic drug treatment through comparison with control cases. The study group comprised 61 children (20 females, 41 males) with epilepsy and a control group was formed of 32 healthy individuals (14 females, 18 males). A spectrophotometric method was used to measure serum prolidase enzyme activity. The mean serum prolidase enzyme activity was 444.70±22.23U/L in the epileptic patients and 366.44±17.43 U/L in the control group. The epilepsy group demonstrated statistically significantly higher prolidase enzyme activity values, when compared with the control group (p=0.003). The serum total oxidant status and oxidative stress index values were measured as statistically significantly elevated in patients with epilepsy compared to the control group (p<0.001 and p=0.000 respectively). However, the serum total antioxidant status was significantly lower in the epilepsy group than in the control group (p=0.032). These results demonstrated that epileptic patients taking anti-epileptic drug treatment had increased serum prolidase enzyme activity and oxidative stress values suggesting that it may show a risk of vascular damage related to increased collagen turnover. Consequently, serum prolidase enzyme activity could be considered a useful oxidative biomarker for evaluation of the subclinical vascular damage in epileptic children.