All-inorganic　dual-phase　CsPbBr3-Cs4PbBr6　quantum　dots　(CPB　QDs)-based　polyacrylonitrile　(PAN)　fiber　synthesized　by　supersaturated　recrystallization　and　electrospinning　technique　possesses　characteristics　of　homogeneous　morphology,　high　crystallinity　and　solution　sensitivity.　Under　365　nm　laser　excitation,　CPB@PAN　fiber　exhibits　surprising　trace-recording　capability　attributing　to　the　splash-enhanced　fluorescence　(FL)　performance　with　a　narrow-band　emission　at　477-515　nm.　In　the　process　of　ethanol　anhydrous　(EA)　and　water　splashing,　the　CPB@PAN　fiber　presents　conspicuous　blue　and　green　emission　when　contacting　with　EA　and　water,　and　maintains　intense　blue　and　green　FL　for　more　than　4　months.　These　experimental　and　theoretical　findings　provide　a　facile　technology　for　the　development　of　biological　protection　display,　biotic　detection　and　moisture-proof　forewarning　based　on　the　trace-recording　performance　of　CPB@PAN　fiber.