Aim: This study investigated the effect of antiepileptic drug monotherapy on cognitive functions in pediatric epilepsy patients. Methods: 98 recently diagnosed epilepsy patients aged 6-16 years were included. All patients underwent routine laboratory tests, electroencephalography, brain magnetic resonance imaging, and intelligence testing. The patients were treated with valproic acid (VA), carbamazepine (CBZ), oxcarbazepine (OXC), or levetiracetam (LEV). The Wechsler Intelligence Scale for Children (WISC-R) was applied three times, before, six months and 12 months after the start of antiepileptic therapy. Results: No significant difference was determined among the mean verbal, performance and total intelligence scores of patients using a single antiepileptic drug at baseline, after six or... 12 months. Conclusion: We conclude that the type of antiepileptic drug using has no adverse effects on cognitive functions.