Mo2N/MoO2 composite nanofibers have been prepared via an electrospinning and controlled nitridation process. The composite nanofibers exhibit a highly efficient Rhodamine B (RhB) absorption behavior with a rate constant of 0.153 g min(-1) mg(-1), which is about 20 times of the commercial-activated carbon material. Furthermore, the nanofibers show stable absorption activity after recycled by an environmental friendly procedure for four times. The excellent absorption performance of Mo2N/MoO2 composite nanofibers demonstrates a promising application of Mo2N-related materials as an absorbent for wastewater treatment.