Considering the small section at the scene of the bridge site erection of a bridge, the temperature have influence on the linear finite element analysis and the longitudinal length of composite beams, in order to advance to determine the temperature effect, is now taking jiuzhou channel bridge steel composite beam of large sections of the Hong Kong, zhuhai and macau bridge section for temperature effect analysis, at the same time, temperature and deflection of continuous monitoring work 24 hours a day. The results show that the composite beams in the overall rise, cooling condition, the vertical deformation is small, the main influence of the axial beam is long.