The extensive use of electrical equipment and portable electronics has aroused major concerns about electromagnetic pollution. Carbon-based polymer composites are widely used in the electromagnetic interference (EMI) shielding field, motivated by their excellent performance. However, the dispersibility between carbon materials and polymers is poor. A large number of researchers used interface design to solve this problem. This article reviews the research on the interface design of carbon filler/polymer composites to enhance EMI shielding performance, and the interface design methods are systematically summarized. After a brief introduction, in Section 1, the EMI shielding mechanism will be briefly discussed in Section 2 to lay the foundation for designing a high-efficiency carbon filler/polymer composite interface. These interface design methods and mechanisms will be discussed in detail in the next section, including interface layer introduction, surface modification of fillers, and in situ polymerization. On the topic of Section 4, the current research on the interface design of carbon filler/polymer composites will be discussed to improve EMI shielding performance of the materials. In the final section, recommendations for further research are put forward, emphasizing that the carbon filler/polymer composites require specific investigations to evaluate interface properties.