In this study, magnetic nickel ferrite/carbon sphere (NiFe2O4/CS) composite was synthesized through hydrothermal strategy. Afterwards, several measurements were conducted to illuminate physicochemical properties of composite. Meanwhile, NiFe2O4/CS was also applied to activate persulfate (PS) for elimination of levofloxacin. The result showed that NiFe2O4/CS composite owned stronger capacity for PS activation than pure NiFe2O4/CS. Furthermore, the influence factors, such as the dosage of catalyst, the concentration of PS and the initial pH, were optimized and analyzed. Also, when the levofloxacin degradation carried out under the optimized condition, with 0.6 g/L NiFe2O4/CS composite and 1.8 g/L persulfate being added and the initial pH being adjusting to 5, 67% levofloxacin was degraded within 1 h. In addition, the possible mechanism of NiFe2O4/CS nanocomposite activating PS was proposed through the radical scavengers and the result of XPS. More importantly, the repeated experiment was conducted for several times, which proved that the NiFe2O4/CS composite owned retrievability and reusability, providing a potentially useful catalyst for contaminants removal in water/wastewater treatment.