In this work, flexible single-walled carbon nanotube/polyaniline (SWNT/PANi) composite films have been synthesized through an in situ electrochemical polymerization/degradation process. In addition to their good flexibility and light weight, cyclic voltammetry (CV) tests revealed that free-standing SWNT/PANi composite films also showed good electrochemical properties. Before electrodegradation, the highest specific capacitance, 501.8 F/g, was obtained for SWNT/PANi composite films with 90 electrochemical polymerization cycles. It reached values up to 706.7 F/g after electrodegradation, an increase of 40%, which was attributed to more available charge-transfer channels and increased polycrystalline PANi regions that were produced by the dissolution of off-lying disordered PANi.