Objective: Although the etiology of attention deficit hyperactivity disorder (ADHD) is unknown, it is thought that endocrine disruptors may be involved in the etiopathogenesis. The aim of this study was to investigate the relationship between ADHD development and exposure to mono-(2-ethylhexyl) phthalate (MEHP), di-(2-ethylhexyl) phthalate (DEHP), and bisphenol A (BPA). Methods: The study included 44 children who were diagnosed with ADHD according to DSM IV-TR diagnostic criteria and 51 healthy children as controls. In all subjects, serum MEHP, DEHP, and BPA were measured by using high performance liquid chromatography (HPLC). Results: Serum MEHP and BPA levels were found to be significantly higher in the ADHD group (0.47 +/- 0.22 mu g/ml, 1.48 +/- 0.28 ng/ml) than the controls (0.31 +/- 0.13 mu g/ml, 0.91 +/- 0.23 ng/ml). There was no difference in the level of DEHP between the ADHD group and healthy controls (2.17 +/- 0.69 mu g/ml, 2.26 +/- 0.56 mu g/ml). Conclusion: Our results could be accepted as an evidence to support an association between BPA, MEHPlevels and ADHD. However, further studies are needed to clarify the linkage between ADHD and endocrine disruptors.