Chloride-induced　steel　corrosion　deteriorates　reinforced　concrete　(RC)　structures,　where　the　interaction　between　passive　film　and　Cl　determines　the　corrosion　resistance　of　the　reinforcement.　Environmental　temperature　changes　have　been　proven　to　significantly　affect　the　ability　of　chloride　ions　to　erode　the　passive　film,　but　the　mechanism　has　not　been　thoroughly　understood.　In　order　to　study　the　effect　of　temperature　change　on　the　microstructure　of　passive　film　nanopores　in　chloride　environments.　This　study　uses　molecular　dynamics　simulation　to　investigate　the　dynamic　properties　of　NaCl　solution　in　the　nanopores　of　passive　film　at　temperatures　of　300　K,　330　K,　360　K,　and　390　K.　Results　show　that　temperature　rise　weakens　the　hydrogen　bond　stability　between　water　molecules　and　the　gamma-FeOOH　substrate,　resulting　in　the　ions　occupying　the　oxygen　sites　of　adsorbed　water　molecules　in　FeO6;　Next,　the　increasing　temperature　also　weakens　the　stability　of　the　hydration　shell　of　ions　in　the　solution　and　accelerates　the　thermal　motion　of　ions,　leading　to　the　increases　in　the　probability　of　ion　collision　with　adjacent　particles　to　form　ionic　pairs;　Otherwise,　within　the　gamma-FeOOH　substrate,　the　interaction　strength　is　reduced　and　the　thermal　vibration　is　enhanced　with　the　temperature,　causing　the　increases　in　chemical　activity,　which　promotes　the　adsorption　of　ions　by　the　substrate.　In　conclusion,　the　temperature　rise　enhances　the　transport　and　adsorption　capacity　of　water　and　ions　in　gamma-FeOOH　nanopores,　and　accelerates　the　failure　of　passive　film.　This　study　provides　a　nano-level　insight　into　understanding　the　effect　of　temperature　on　the　durability　of　passive　films　in　chloride　environments,　which　can　be　used　for　the　antirust　treatment　of　steel　in　high-temperature　environment.