In the present study, CNT-embedded electric heating composites were fabricated and the effects of silica aerogel addition on the electric heating capabilities and heat-induced electrical stability were examined. Silica aerogel at levels of 0%, 0.5%, and 1.0% by mass of polymer were incorporated into the polymeric composites incorporating 4% CNT. The fabrication details, tunneling-induced electrical characteristics, and electric heating capabilities during cyclic and long-term heating conditions were reported. The electric heating test results were discussed in terms of the SEM observations, thermal images taken during the heating process, and schematic descriptions of the heating process. The test results showed that the incorporating silica aerogel could reduce the redistribution of the individual CNT particles, improving the electric heating capabilities including the heat generation stability and the heat-induced electrical stability during the heating process. Moreover, incorporating silica aerogel increased the cooling time, and improving the heat-storage capability related to the heating efficiency. Thus, it can be concluded that the silica aerogel addition has clear potential to improve the electric heating capability and heat-induced electrical stability of CNT-embedded electric heating composites.