In the modern bridge construction control,the application of artificial neural network BP algorithm is practically used to solve the calculation of temperature field,with the On-site temperature test data.Based on the measured temperature data of the HU LU WAN Bridge,and by using mature BP network model and MATLAB,the mapping relationship between input and output is established.Some key factors on temperature field are analyzed and a method with less number of input nodes and high calculating speed is studied.The calculated temperature field is significant for the temperature field simulation of the whole bridge and its construction.