The aim of this study was to evaluate vitamin B12 and folate levels, thyroid functions, sex hormones and bone mineral density in idiopathic epileptic patients taking oxcarbazepine as monotherapy. Newly diagnosed pediatric patients with idiopathic partial epilepsy taking oxcarbazepine (OXC) as monotherapy were enrolled in this study. The pre-treatment and 6 months post-treatment values of vitamin B12, folate, thyroid functions, sex hormones, and bone mineral density (BMD) were obtained from all patients. A total of 32 patients (22 (68.8%) males and 10 (31.2%) females) were included in this study. The mean age was 7.4 ± 3.2 years (range: 2–14 years). There were no significant differences between the pre-treatment and 6 months post-treatment values of vitamin B12, folate, thyroid functions, sex hormones, and BMD. However, the 6 month post-treatment sex hormone binding globulin (SHBG) values (159.92 ± 48.14 nmol/L) were significantly higher than the pre-treatment values (137.88 ± 43.12 nmol/L) (p=0.009). We found that OCX treatment in children did not have an effect on serum folate and vitamin B12 levels, thyroid functions, sex hormones and BMD but caused increased SHBG. Over time, the increase in serum SHBG levels may lead to diminished bioactivity of sex steroids, and thus to reduced fertility. The further studies are needed to demonstrate the clinical importance of increased SHBG levels.