Carbon and iron co-doped titanium dioxide catalyst carried on activated carbon (Fe-C-TiO2/AC) was successfully synthesizedusing 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 show that, with the appropriate amount of activated carbon, prepared catalysts Fe-C-TiO2/xAC showed the high catalytic activitiesand Fe-C-TiO2/12AC sample showed the best performance. Catalysts carried on AC and modified by HNO3 and PSS have better efficiency than non-modified one.