As　a　promising　electrochromic　material,　WO3　frequently　suffers　from　the　cyclic　degradation　caused　by　trapped　ions　in　the　host　structure.　The　intrinsic　trapped　sites　in　WO3　host　structure　usually　are　considered　as　the　main　contribution　to　the　formation　of　trapped　ions.　In　this　study,　by　chronopotentiometry　technology　to　quantify　the　diffused　ions,　we　find　that　ions　transport　behavior　plays　a　key　role　in　the　structural　stability　and　the　generation　of　trapped　ions.　Specifically,　repeated　insertion/extraction　behavior　will　result　in　WO3　structure　damage.　As　a　result,　the　ions　transport　shows　hysteretic　kinetics　in　the　subsequent　reaction　process,　and　the　inserted　Li+　ions　in　the　coloration　process　can　not　be　completely　extracted,　which　contributes　to　the　generation　of　the　majority　of　trapped　ions　in　film.　Subsequently,　the　transmittance　of　the　bleaching　state　and　the　optical　modulation　ability　of　WO3　film　show　serious　decay.　This　work　exhibits　a　new　understanding　of　the　degradation　of　electrochromic　materials　and　offers　an　efficient　method　for　WO3　to　maintain　a　long-life　performance.　(C)　2020　The　Electrochemical　Society　(＂ECS＂).　Published　on　behalf　of　ECS　by　IOP　Publishing　Limited.