Flexible　scintillator　screens　with　environmental　stability,　high　sensitivity,　and　low　cost　have　emerged　as　candidates　for　X-ray　imaging　applications.　Here,　a　large-scale　and　cost-efficient　solution　synthesis　of　the　vacancy-ordered　double　perovskite　Cs2ZrCl6,　which　is　characterized　by　thermal　activation　delayed　fluorescence　(TADF)　dominated　by　triplet　emission　under　X-ray　irradiation,　is　demonstrated.　The　large　Stokes　shift　and　efficient　luminescence　collection　of　TADF　effectively　ensure　the　light　outcoupling　efficiency.　Further,　flexible　X-ray　scintillator　screens　with　an　area　of　400　cm(2)　are　prepared　using　poly(dimethylsiloxane)　(PDMS)　as　the　carrier,　exhibiting　excellent　scintillation　properties　with　light　yields　as　high　as　49　400　photons　MeV-1,　spatial　resolutions　up　to　18　lp　mm(-1)　and　detection　limits　as　low　as　65　nGy　s(-1).　Finally,　the　high-quality　imaging　results　of　non-planar　and　dynamic　objects　by　such　screens　are　demonstrated.　It　is　believed　that　the　explored　Cs2ZrCl6@PDMS　flexible　scintillator　screens　would　offer　a　big　step　toward　expanding　the　application　range　of　scintillators　in　different　environments.