Carbon fiber (CF) is expected to improve the fuel efficiency of automobiles by reducing the weight of body, but a large amount of energy is required for manufacturing of original CF, so the reuse of CF is essentially important from an environmental impact perspective. Challenging the complete decomposition of CFRP for getting a reused CF has been researched by using oxidizing active species such as peroxide-sulfuric acid obtained from the electrolysis of concentrated sulfuric acid to obtain a high-performance reused CF. In this study, concentrated sulfuric acid containing oxidizing active species produced by the electrolysis of sulfuric acid had the completely ability to be dissolved a matrix resin component of CFRP in a short period of time, and a getting reused CF showed an equivalent mechanical performance to that of original CF. This CFRP recycling pr ocesses by using electrolyzed sulfuric acid seemed to be the excellent method to get a high-performance reused CF.