Based on the results of continuous observations of the longitudinally connected ballastless track on curved bridges, the time-dependent deformations of vertical temperature gradient in different kinds of weather were discussed. Based on statistics and curve-fitting, raised temperature load models were fit for typical areas in our country. The analysis results reveal that the changing of the temperature in the track structure is fast, the temperature changing value of surface was 16.0℃ in maximum and 8.0℃ in average, the temperature changing value became small, and the time of maximum temperature come late with the increase of distance to surface, and at the bottom of the track structure, the temperature changing value was 1.5 ℃ in maximum, 0.8 ℃ in average, the fitting curve of vertical temperature gradient in longitudinally connected ballastless track on curve bridge can be exponential curve, and the distribution law matches the provisions about the vertical temperature gradient of the code for the design of railway bridges and culverts in China.