The　demand　for　high-temperature　scintillator　detectors　in　petroleum　exploration,　space　exploration　and　other　fields　is　considerable.　However,　common　high-temperature　scintillator　detectors　based　on　NaI(Tl)　exist　many　issues　such　as　poor　humidity　stability　and　complex　processing.　In　this　study,　we　present　Cs2Na(Er0.4Yb0.6)Cl6　double　perovskite　as　a　promising　alternative,　demonstrating　its　resistance　to　thermal　quenching　within　the　range　of　room　temperature　to　500　K.　The　double　perovskite　scintillator　shows　a　light　yield　of　20,000　photons/MeV　at　500　K,　because　of　the　cross-relaxation　between　Yb　and　Er　ions.　By　mixing　Cs2Na(Er0.4Yb0.6)Cl6　with　polydimethylsiloxane　(PDMS),　we　produced　a　flexible　film　boasting　a　resolution　of　12　lp/mm.　Notably,　this　film　demonstrates　better　imaging　performance　under　high-temperature　conditions　compared　with　that　of　under　room　temperature,　showcasing　its　potential　for　high-temperature　imaging　applications.　Moreover,　our　findings　offer　insights　into　the　design　of　novel　scintillators　resistant　to　thermal　quenching.　©　2025　Elsevier　Inc.