Carbon and iron co-doped titanium dioxide catalyst carried on activated carbon (Fe-C-TiO2/AC) was successfully synthesized using the sol-gel method and then treated by hydrothermal treatment. Activated carbon (AC) was modified by HNO3 and poly (sodium styrene sulfonate) (PSS) before being carried on the catalyst. The composite was characterized by XRD, UV-VIS spectrophotometry, IR, SEM and BET. The performances of the supported catalysts have been evaluated for the degradation of Rhodamine B (RhB) solution under visible-light irradiation. Results showed that, catalysts carried on AC and modified by HNO3 and PSS have better efficiency than AC virgin. The optimum dose of the photocatalyst was 1.6 g/l for the degradation of Rhodamine B (20 mg/l).