In this work the effects of electropolymerization conditions on the morphological properties and conductivity of poly(3,4-ethylenedioxythiophene) (PEDOT) film have been studied. PEDOT films were electrochemically synthesized in a one step process from acetonitrile solution containing 3,4-ethylenedioxythiophene (EDOT) and lithium perchlorate. Based on atomic force microscopy, scanning electron microscopy, cyclic voltammetry and impedance spectroscopy measurements, the morphological properties such as the of structure, double layer capacitance and thus the polymer surface area have been determined. It was shown that depending on the deposition conditions applied, different structures and film surface area could be obtained. Impedance measurements performed during deposition showed different resistance behavior and conductivity. The relationship between structure and conductivity of PEDOT film obtained under different deposition conditions has been discussed. (C) 2015 Elsevier Ltd. All rights reserved.