To eradicate antibiotics from aqueous solution, cerium(Ce) doped ZnFe₂O₄ microspheres with different Ce mass ratios were prepared by a hydrothermal method and applied for the photocatalytic decomposition of tetracycline antibiotic. The results reveal that the introduction of Ce improves the charge separation for the photogenerated electron-hole pairs, which can be confirmed form the photocurrent spectra. The optimized sample ZnFe_1.96Ce_0.04O₄ shows a decomposition rate of 56.6% under simulated solar light within 40 min. The trapping experiments show that hydroxyl radical and superoxide radical are the main degrading species, directly involving in the decomposition of antibiotics. Moreover, the rate of hydrogen produced from water splitting photocatalyzed by ZnFe_1.96Ce_0.04O₄ reaches 230.4μmol/(g·h) under simulated solar light irradiation.