The　CeO2/CuMoO4type　II　heterojunction　with　varying　CeO2contents　was　synthesized　by　the　hydrothermal　method.　These　heterojunction　catalysts　exhibit　superior　antibacterial　activity　against　both　Escherichia　coli　and　Staphylococcus　aureus　under　visible　light　irradiation　compared　to　CuMoO4alone.　The　evaluations　of　bacterial　morphology,　intracellular　content　concentration　of　bacteria,　and　reactive　oxygen　species　(ROS)　during　the　photocatalytic　process　indicated　that　the　ROS　oxidize　phospholipids　in　the　bacterial　cell　membrane,　which　leads　to　the　damage　of　the　cell　structure　and　leakage　of　cell　contents,　ultimately　resulting　in　bacterial　inactivation.　Both　EPR　(Electron　Paramagnetic　Resonance)　and　ROS　scavenging　experiments　confirmed　that　superoxide　radicals　(·O2–)　and　e–play　an　important　role　in　the　photocatalytic　antibacterial　activity.　The　introduction　of　CeO2into　CuMoO4enhances　the　heterojunction’s　photoelectric　performance　and　promotes　the　efficient　separation　of　photogenerated　carriers,　which　benefits　the　production　of　·O2–.　Furthermore,　the　Ce3+/Ce4+redox　couple　that　exists　in　CeO2may　act　as　a　trap　to　capture　the　electron,　which　inhibits　the　recombination　of　electrons　and　holes,　and　further　reacts　with　the　adsorbed　oxygen　on　the　catalyst　surface　to　generate·O2–.　This　approach　of　introducing　Ce3+/Ce4+redox　pairs　as　defect　centrals　to　improve　superoxide　radicals　offers　an　avenue　for　modifying　photocatalytic　materials　and　provides　an　alternative　way　to　traditional　antibiotic　strategies　in　antibacterial　applications.　©　2025　American　Chemical　Society