Abstract: The interface is a bridge connecting different two phases inside the composite material, which greatly affects the thermal, electrical, mechanical and other properties of the composites. As a new branch in the field of composite materials, thermal conductive composites have attracted more and more attention in recent years due to the rapid development of electronic and electrical appliances. However, it is found that the thermal conductivity of the composites is difficult to reach a few percent of the thermal conductivity of the conductive filler even if the high packing scheme is adopted, and the interfacial thermal resistance is the key factor affecting the improvement of the thermal conductivity of the composites. This paper analyzes the reasons for the thermal resistance of the internal interface inside the composites from the perspective of the interface layer and the heat transfer effect of the interface. In addition, the influence of interface effects on the heat conduction of functional composites was discussed in terms of theoretical research methods, experimental characterization techniques, and interface factors that affect the internal heat conduction behavior of materials. Finally, the development of interface and interfacial heat transfer research were summarized and prospected.