Failure criteria of axially loaded steel columns under fire are introduced in this paper.Critical temperatures of steel columns are analyzed numerically according to different failure criteria.Mechanical properties of steel at elevated temperature are calculated by EC3and CECS

respectively.Comparisons are made among different predicted results according to different failure criteria.The study shows that:（1）two deformation criteria give generally the same results

both overestimate critical temperatures;（2）it is worth to be noticed that the deformation criteria are only applicable under the condition that the global failure occurs;（3）mechanical properties of steel at elevated temperatures have significant influence on critical temperature of axially loaded columns

more than 200°C differences are observed between temperatures predicted by EC3and CECS.The upper and lower limits of critical temperatures for axially loaded steel columns are provided for convenient use.