Background: Renal disorders have been observed with the long-term treatment of some antiepileptic drugs (AEDs). We aimed to compare the effects of carbamazepine (CBZ) and valproate (VPA) on renal function in children with epilepsy. Methods: This quasi-experimental study included children with epilepsy aged 2 months to 14 years who had persistently been receiving CBZ or VLP monotherapy for more than 6 months and were referred to Bandar Abbas Children’s Hospital, Bandar Abbas, Iran, 2019-2020. Demographic features, including age and sex, as well as family history of epilepsy, disease duration, and duration of treatment were recorded for each patient. Random blood and urine samples, along with 24-hour urine samples were collected from all the participants. Blood urea nitrogen (BUN), sodium, alkaline phosphatase (ALP), and pH were measured in blood samples. Glucose, protein, sodium, potassium, phosphorus, and creatinine were estimated in 24-hour urine samples. N-acetyl-beta-D-glucosaminidase (NAG) and pH were assessed in random urine samples. Results: Of the 80 children in this study with a mean age of 7.43±3.22 years, 58 (72.5%) were males. Children in both groups were comparable in terms of age, sex, family history of epilepsy, and disease and treatment duration. The urine NAG level was significantly higher in the VPA group compared to the CBZ group (P=0.010). Further, 24-hour urine protein and glucose levels were significantly higher in the VPA group. As for blood parameters, except for sodium (P=0.034), ALP (P<0.001), and pH (P=0.006) which were significantly higher in the CBZ group, other parameters were significantly higher in the VPA group. Conclusion: Overall, CBZ appears to be safer than VPA regarding its effects on renal function in children treated for epilepsy.