Abstract: In this paper, the monitoring data, which contain the road surface temperature, air temperature, wind speed, wind direction, relative humidity, precipitation observed at the traffic automatic weather stations named as Hurongxi, Hanyi,Wuhuang and Huanghuang on the Huyu expressway during the period from June 2013 to August 2014, are used to investigate the characteristics of the road surface temperature in different seasons and different sky conditions. The forecast model of the maximum and minimum road surface temperature are established for different sections by statistical analyses, and the forecast results are verifed. The results show that the road surface temperature and air temperature at Hurongxi, Hanyi, Wuhuang and Huanghuang stations display obvious diurnal variation as well as the difference between the road surface temperature and air temperature display differently. Compared with the other three sections, the maximum difference between the road surface temperature and air temperature at Hurongxi increases in winter and decreases in summer overall. The road surface temperature is close to air temperature at Hurongxi after sunset on sunny to cloudy and overcast days in winter, while less than air temperature at Hanyi, Wuhuang and Huanghuang. The air temperature is less than road surface temperature at the four stations on rainy days,of which the most signifcant at Hurongxi. In summer, the air temperature is less than road surface temperature at the four stations on three types of sky conditions and the difference between both is the biggest in afternoon on sunny to cloudy and overcast. The road surface temperature is very close to each other among the four stations in January, while become different with the decrease of altitude in April, July and October. The forecast results of the road surface temperature were nearly close to the actual observations at Hurongxi and Huanghuang. So they may be used as references. But there were some big errors between the forecasts and observations at particular times at Hanyi and Wuhuang stations, the forecasts should be corrected for actual business.