The work aims to prepare the cellulose nanofibers/carbon fibers-polyaniline/carbon nanotubes (CNFs/CFs-PANI/CNTs) supercapacitor electrode, with CNFs/CFs composite film as the conductive substrate. CNFs/CFs composite film was prepared by ultrasonic treatment and vacuum filtration. In-situ polymerization was performed to prepare polyaniline (PANI) and polyaniline/carbon nanotubes (CNTs) composites. CNFs/CFs-PANI and CNFs/CFs- PANI/CNTs electrodes were prepared through vacuum filtration method. CFs formed conductive interpenetrating networks in the CNFs/CFs composite film, which was a good conductive substrate of supercapacitor electrode. The CNFs/CFs-PANI/CNTs electrodes exhibited good electrochemical performances. When the scan rate was 5 mV/s and the capacitive performance was 380.74 F/g, the stable cycling performance was 88.05% of initial capacitance after 1000 cycles. With the CNFs/CFs conductive composite film as the substrate, the CNFs/CFs-PANI/CNTs electrodes prepared have good electrochemical performance and can be used as the supercapacitor electrodes.