N doped TiO2/NiFe2O4/diatomite (NND) photocatalytic composite was fabricated via a facile two-step sol-gel method. Its crystal structure, morphology, specific surface area, pore size distribution and magnetic property were systematically characterized and analyzed. The photoactivity of NND was investigated via the degradation of Rhodamine B (RhB) solution under visible light irradiation. NND achieved high photodegradation efficiency due to the synergy between adsorption of diatomite (Dt) and degradation of TiO2, as well as the synergy between TiO2 and NiFe2O4. NND could be simply separated from aquatic environment using an external magnet, due to the ferromagnetism of NiFe2O4. We consider that NND is applicable for wastewater treatment. (C) 2017 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.