Carbon fibers (CF) have been widely used in recreational equipment, aircraft and space exploration etc. because of the advantages such as high stiffness and specific strength and heat resistance. However the film adhesive strength between CF and polymers is weak because there is no functional groups such as hydroxyl, amine and carboxyl groups on CF surface. Therefore many studies have been conducted to improve it. In this study, CF surface treatment using wet process was performed to enhance the interfacial strength between CF and polymer. The treated CF surface has hydrophilic functional groups such as hydroxyl and carboxyl groups. This enhanced the dispersibility in water and improved the adhesive strength between CF and polymers by modifying the degree of chemical bonding with resin. Then carbon papers using treated CF were manufactured using wet-laid process. And the carbon papers and polymers composite could be obtained by film lamination method. The treated CF surface was characterized by fourier transformed infrared spectroscopy (FT-IR) and raman spectroscopy. The dispersibility of CF in carbon papers was measured using scanning electron microscope (SEM). And the mechanical properties of the composites were also measured to verify the effect of surface treatment.