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Novel magnetically separable BiOBr/NiFe 2 O 4 composite photocatalysts with different mass ratios were fabricated through a facile hydrothermal treatment. The phases, morphologies and photophysical properties of the as-obtained samples were characterized by X-ray diffraction (XRD), energy dispersive spectrometry (EDS), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microcopy (TEM) and diffuse reflection spectroscopy (DRS). Their visible light photocatalytic performances were examined by degradation of methylene blue (MB) and phenol. Compared with bare BiOBr and NiFe 2 O 4 , all heterostructured BiOBr/NiFe 2 O 4 nanocomposites exhibited significantly enhanced photocatalytic efficiency. The BiOBr/NiFe 2 O 4 -20% composite showed the highest photodegradation capacity, which was about 3.2 and 22.4 times greater than that of individual BiOBr and NiFe 2 O 4 , respectively. The degradation efficiency of BiOBr/NiFe 2 O 4 -20% in the degradation of MB dye hardly changed after five cycles, signifying that the BiOBr/NiFe 2 O 4 -20% photocatalyst had excellent recyclability. In addition, BiOBr/NiFe 2 O 4 composite photocatalysts could be easily separated from contaminant solution by using a magnet and recycled, exhibiting great potential for application in the fields of environmental purification of organic pollutants and wastewater treatment. In the light of experimental results, we proposed a photocatalytic mechanism which confirmed that the enhancement of photocatalytic performance for BiOBr/NiFe 2 O 4 composites was mainly ascribed to the efficient separation of photo-induced charges resulting from the well-known “heterostructure effect” between NiFe 2 O 4 nanorods and BiOBr nanosheets. [ABSTRACT FROM AUTHOR]