Aiming at the problems of the destroyed structure, the decreased capacitance retention rate and the bad cycle stability of polyaniline (PANI) during the continuous charge/discharge due to the irreversible deformation of PANI, this article proposes that the TEMPO-oxidized cellulose nanofiber (TOCNF), doping sulfonated multi-walled carbon nanotube (SMWCNT) enhances its electrical conductivity, the microstructure of the polymer is controlled via in-situ polymerization of the aniline on the surface of TOCNF-SMWCNT, the composite electrode materials PANI/(TOCNF-SMWCNT) is synthesized. The composite electrode materials were characterized by SEM, TEM, XRD, XPS, FTIR, and Raman, and the structure-activity relationship of the enhanced electrical properties was also clarified. The test results showed that the specific capacitance of PANI/(TOCNF-SMWCNT) is 546.0 F/g at a current density of 1.0 A/g. In addition, the composite electrode exhibited good cyclic stability with retention of 82.4% even after 5000 cycles when the current density is 1.0 A/g.