Stainless　steel　is　increasingly　used　in　renewable　energy　sectors　due　to　its　advantageous　mechanical　properties,　corrosion　resistance,　and　aesthetic　appeal.　However,　exposure　to　high　temperatures　can　significantly　alter　these　properties,　potentially　compromising　long-term　performance　in　renewable　energy　infrastructure.　This　study　investigates　the　effects　of　ISO　834　standard　fire　on　the　constitutive　behavior　of　austenitic　304　stainless　steel　through　experimental　analysis.　The　findings　indicate　that　cross-sectional　weakening　has　a　minimal　impact　on　the　post-fire　degradation　of　stainless　steel　structures.　After　sufficient　cooling,　the　elastic　modulus　and　strain　hardening　index　of　fire-exposed　stainless　steel　are　restored　to　pre-fire　levels.　However,　both　the　nominal　yield　strength　and　ultimate　strength　are　significantly　diminished　after　fire　exposure,　with　these　reductions　being　positively　correlated　with　heating　duration.　Practical　formulas　are　provided　for　predicting　the　nominal　yield　strength,　ultimate　strength,　and　ultimate　strain　of　stainless　steel　after　ISO　834　standard　fire.　Additionally,　a　stress-strain　constitutive　model　has　been　developed　that　accurately　predicts　the　full　strain　range　observed　in　post-　fire　tensile　tests　of　austenitic　304　stainless　steel.