Poly(3,4-ethylenedioxythiophene) (PEDOT) with three-dimensional (3D) flowerlike nanostructures was fabricated by chemical oxidation polymerization in a ternary phase system, which was composed of the surfactant sodium bis(2-ethylhexyl) sulfosuccinate (AOT), aqueous FeCl3 solution and p-xylene. This kind of 3D flowerlike PEDOT formed by nanofibers was prepared by controlling the molar ratio of water (used to dissolve FeCl3) to the surfactant, AOT. This molar ratio is defined as N which equals nH2O/nAOT. In particular, both the conductivity and specific surface area increased with the molar ratio, N, increasing. The room temperature conductivity of the synthesized PEDOT reached a relative high value of 137 S cm−1. Moreover, the novel 3D flowerlike nanostructures endow a high specific surface area of around 46 m2 g−1. The measurements of UV-visible spectroscopy (UV-vis) and X-ray photoelectron spectroscopy (XPS) indicate that the doping level played a key role in improving conductivity of PEDOT. This study is significant to the potential applications of PEDOT on supercapacitors, sensors, actuators, transistors, and so on.