Abstract: The continuous cooling transformation ( CCT) curves of U75V steel (/% ； 0. 75C, 0. 63Si, 0. 95Mn, 0. 025P,0. 004S,0. 26Cr,0. 05V) are measured by a Gleeble-3500 thermal simulation testing machine, and the calculated model for temperature field and structure transformation of 60AT rail during air-cooling process after rolling is established by using DEFORM-3D finite element software to study and analyze the effect of temperature and structure on bending deformation of 60AT rail during 150 ~700 s air-cooling process after rolling. Results show that the effect of great volume to surface- area ratio of rail waist of 60 AT rail on distribution of temperature at whole rail section is larger, with rail air-cooling for 150 s, there is no phase transformation at section of 60AT rail and the structure is all austenite, with temperature dropping i. e. air cooling for 650 s, the 97. 2 % austenite at rail section transfers to pearlite, besides the effect of structure transformation on bending deformation of rail is larger, at end air-cooling the bending deflection of rail in K-direction (lateral bending) is -0. 07 mm, i. e. the bending is toward rail bottom short edge, and the bending deflection of rail in Z-direction (positive bending) is 0. 228 mm, i. e. the bending is toward rail head. The calculation results are available for reference of pre-bending in rail straightening process.