Fire dynamics,heat transfer and finite element analysis method were used to obtain the fire resist-ance of airport terminal steel structure.First,the credible and most dangerous fire scenarios of airport terminal roof were adopt.Then,the fire dynamics software FDS and the heat transfer formula were used to get the tem-perature rise curves in the fire affected region.Finally,the model of the structure was set up by finite element method,the load conditions and temperature rise curves were combined to calculate the mechanical properties of the structure.The resulit shows that the internal force of some members in the structure are increased and e-ven close to the design strength,but the vertical displacement of the structure is relatively small to the overall span of the structure,the structure is still in safe condition.From the perspective of overall security,it is effi-cient to carry out the fire-resistant design of structure by its own strength,and to improve the fire-resistant properties of the structure by strengthening the integrity and increasing the number of statically indeterminate.