In order to determine the in situ actual thermal conductivity of steel fiber ceramsite concrete （SFCC）， specimens were made synchronously with the construction of bridge deck and measured by the hot-plate method. The existing thermal conductivity prediction equation was verified and extended. Measurement and numerical simulation of temperature field of bridge deck during high temperature asphalt paving were carried out. The results show that when environment humidity is 67%， the measured thermal conductivity of SFCC is between 0.915-1.409 W/（m · K）， and the increase of steel fiber will improve the thermal conductivity. Considering the environmental humidity and effect of steel fiber， the extend Maxwell equation prediction results agree well with test results. The temperature variation of SFCC under high temperature paving can attend 20.5 ℃， which is more unfavorable than daily temperature difference in the specification. The numerical simulation method can effectively calculate the temperature gradient of the bridge deck.