The thermal conductivity enhancement factor is used to indicate the efficiency of heat conduction of the tested material. In this research, it serves as a measure of the increased efficiency of the asphalt specimen after the addition of the reinforcing material. From Figures 4(a) and 4(b), it is evident that the thermal conductivity enhancement factor (K) of the asphalt specimens, with varying proportions of the additive, undergoes significant changes. The addition of graphite clearly increases the K values [14]. When increasing graphite content by 1% and 2%, the most suitable proportion observed is 1% by weight. The value decreases as the proportion of graphite is further increased. The addition of steel fibers also contributes to an increased thermal conductivity (K value) of the asphalt specimen [8]. When comparing the K values of asphalt specimens mixed with steel fiber at 1% and 2% by weight, similar results are observed, with asphalt specimens containing 2% steel fiber showing slightly better performance than those with 1% steel fiber. However, both of these values still remain lower than those of the specimens mixed with graphite.