Magnetically recyclable C-doped TiO2/ Fe3 O4 (C-TiO2/ Fe3 O4 ) nanocomposite was successfully synthesized via a sol-gel method. The synthesized samples were characterized using SEM, energy-dispersive X-ray spectroscopy (EDS), FTIR, and UV-VIS di use reflectance spectroscopy (DRS) techniques. The results clearly showed that a C-TiO2/ Fe3 O4 nanocomposite was produced. The photocatalytic activities of the prepared pristine (TiO2 ), C-doped TiO2 (C-TiO2 ) and C-TiO2/ Fe3 O4 were evaluated by the photodegradation of methyl orange (MO) under natural sunlight. The e ect of catalyst loading andMOconcentration were studied and optimized. The C-TiO2/ Fe3 O4 nanocomposite exhibited an excellent photocatalytic activity (99.68%) that was higher than the TiO2 (55.41%) and C-TiO2 (70%) photocatalysts within 150 min. The magnetic nanocomposite could be easily recovered from the treated solution by applying external magnetic field. The C-TiO2/ Fe3 O4 composite showed excellent photocatalytic performance for four consecutive photocatalytic reactions. Thus, this work could provide a simple method for the mass production of highly photoactive and stable C-TiO2/ Fe3 O4 photocatalyst for environmental remediation.