Polyaniline nanofibers (PANI-NFs)/graphite oxide (GO) nanocomposites with excellent interfacial interaction and elongated fiber structures were synthesized via a facile interfacial polymerization method. This method efficiently exfoliated the expanded layer structure of GO into individual sheet and thus significantly enhanced the specific surface area. The reduced diameter of PANI-NFs in PANI-NF/GO than that of pure PANI-NFs could shorten the diffusion distance and enhance the electro-active sites. The PANI-NFs/GO hybrid materials showed orders of magnitude enhancement in capacitance and better cycling stability than that of individual GO and PANI-NF components.