Dendritic polyaniline nanofibers and submicrometer-sized fibers have been synthesized by chemical oxidative polymerization of aniline (An) doped with salicylic acid (SA). The diameters of the fibers could be controlled easily from 30 to 400 nm by varying the concentration of aniline and salicylic acid at room temperature. Scanning electron microscopy (SEM) and typical transmission electron microscopy (TEM) were applied to investigate their morphologies. Fourier transform infrared (FTIR) spectrum indicated that the state of the dendritic polyaniline fibers is emerialdine rather than solely the leucoemeraldine or permigraniline forms. The dendritic polyaniline fibers have potential applications as chemical sensors or actuators and neuron devices.