The various morphologies of polyaniline are grown on carbon fibers derived from natural hollow cellulose by in situ polymerization of aniline. The morphologies of nanofibers, pyramid-like, nanorods and nanowires can be facilely controlled by the doping of hydrochloric acid, sulfuric acid, perchloric acid, phosphoric acid and p-toluenesulfonic acid, respectively. The perchloric acid doped composite shown the maximum specific capacitance of 580 F g⁻¹ at 1.0 A g⁻¹. Remarkably, the all solid-state supercapacitors based on this sample deliver a maximum energy density of 13.3 Wh kg⁻¹. The excellent performance is attributed to the unique morphology and hollow structure of the conductive substrate, which can drastically facilitate the ion diffusion and improve the utilization of the electroactive.