One modern method to improve pavement thermal performance is using induction heating or microwave radiation. Asphalt mixtures have low thermal conductivity due to the insulating nature of aggregates and bitumen. This causes a severe temperature gradient between the surface and depth of the asphalt layer when heated by microwaves. To overcome this, using various additives to create a uniform heat transfer network has attracted many researchers. The main objective of this study is to investigate the effect of styrene-butadiene-styrene (SBS) and carbon fibers (CF) on heating rate and temperature distribution of asphalt samples under microwave radiation and to evaluate their mechanical properties. To study the heating process, asphalt samples were placed in a microwave for 30, 60, 90, 120, and 150 seconds, and the temperature on the surface and inside the samples was examined. Results showed that carbon fibers increase heating rate and provide more uniform temperature distribution than the control sample, while SBS reduced the average surface and internal temperature and weakened temperature distribution uniformity. Furthermore, a three-point bending test was used to evaluate and compare the effect of these additives on mechanical properties. Results showed that SBS increases sample strength by 180% compared to control samples. Carbon fibers reduced asphalt sample strength by approximately 21% compared to control samples. Overall, samples made with both SBS and CF have better performance than other asphalt samples; they have a strength about 164% of control samples, as well as more uniform temperature distribution and higher heating rate.