The　electric　field-modulated　photoluminescent　(E-PL)　effect　has　received　much　attention　because　of　its　potential　applications　in　optical　data　storage　and　communication.　Based　on　the　E-induced　antiferroelectric-ferroelectric　(AFE-FE)　phase　transition,　a　large　and　reversible　modulation　of　the　PL　intensity　was　previously　realized　in　lanthanum-doped　Pb(Zr0.9Ti0.1)O3　(PLZT)　ceramics.　However,　such　systems　contain　abundant　leads　and　are　thus　toxic　to　humans　and　the　environment.　In　this　work,　Er-doped　AgNbO3　(ANO)　lead-free　ceramics　were　prepared,　and　their　E-PL　effect　was　investigated.　From　the　perspective　of　the　crystallographic　symmetry,　the　reversibly　Einduced　orthorhombic　Pbcm　to　orthorhombic　Pmc21　transition　results　in　a　negative　PL　intensity　change　of　25%,　which　is　different　from　the　positive　30%　PL　modulation　in　the　PLZT　system　triggered　by　the　AFE-FE　orthorhombic-rhombohedral　phase　transition.　This　symmetry-dependent　negative　PL　modulation　in　ANO　ceramics　enriches　the　understanding　of　the　E-PL　effect　in　AFEs　and　provides　an　environmentally　friendly　alternative　for　multifunctional　optoelectronics.