For the first time, novel polyaniline (PANI)–cellulose filament fibers have been successfully spun from hydrophobic PANI and hydrophilic cellulose complex solution dissolved in aqueous containing 7 wt% NaOH/12 wt% urea as the solvent by wet-spinning. The composite fibers had a circular cross-section and homogenous surface structure, as a result of good miscibility between PANI and cellulose associated through hydrogen bonds. Moreover, at low PANI content, the composite fibers realized a transition from an insulator to a semiconductor. This work has provided a simple and eco-friendly avenue for the production of PANI composite fibers that have great potential applications in the antistatic textile and military industries.