Nanocrystal　scintillators　have　attracted　considerable　attention　due　to　their　attractive　facile　solution-processed　thin-film　fabrication　and　tunable　X-ray　luminescence,　and　thus　hold　promise　for　manufacturing　next-generation　scintillation　screens　for　high-resolution　X-ray　imaging.　Current　inorganic　scintillators　usually　have　drawbacks　of　time-consuming　preparation,　toxic　components,　and　rigorous　synthesis　conditions　at　a　relatively　high　temperature.　Here,　we　report　a　one-pot　green　synthesis　strategy　for　readily　scaling-up　preparation　of　eco-friendly,　lanthanide-doped　NaBiF4　nanoscintillators.　These　nanoscintillators　feature　efficient　X-ray　absorption　due　to　the　high-Z　bismuth　element　and　tunable　radioluminescence　in　the　visible　region　through　rational　lanthanide　doping.　We　demonstrate　a　laminating-annealing　technology　to　fabricate　large-area　scintillation　screen　(Ø　=　5　cm)　using　these　NaBiF4　nanoscintillators　for　high-resolution　X-ray　imaging　with　a　spatial　resolution　of　9　line　pairs　per　millimeter　(lp　mm−1).　Our　study　offers　new　ways　to　transport　low-cost　synthesis　of　high-quality　nanoscintillators　for　high-performance　digital　radiography.　©　2022