Large area exposure of bare soils caused by soil erosion has serious impacts on the regional ecological environment, such as the rise of land surface temperature (LST). As a typical reddish soil erosion region in southern China, the hilly area in County Changting has been called flame hilly area because of extensively exposed reddish soils and hot weather in the area. This study utilizes remote sensing technology to investigate dynamic of soil exposure intensity (SEI) and accompanied soil heat flux and LST changes during the period from 1988 to 2010 in the county. Results show that owing to the 22-year treatment of soil erosion, the SEI in the main soil loss areas of the county has declined by 20.26%, high SEI area has reduced by 81.95%, and soil heat flux has decreased by 33.28%. All of these have contributed to the decrease in LST differences between exposed and vegetated areas by 20.8% during the study period. This indicates an improvement of the thermal environment in the flame hill area once severely exposed. Detailed quantitative relationship analysis can find that (1) SEI is positively linearly correlated with soil heat flux and LST and (2) each decrease in SEI by 0.1 unit in the future would reduce LST difference by 0.88 °C (or 1.01 °C when accompanied by an equal increment in fractional vegetation cover).