Abstract: This review introduces the recent reports on polymer-based electromagnetic shielding materials. The shielding mechanism and shielding effectiveness of polymer-based electromagnetic shielding materials with different structures (porous structure, segregated structure and layered structure) and other special structures are summarized and analyzed emphatically. Compared with the composite materials with uniformly distributed fillers in the polymer matrix, the structure design can enrich, re-orient and connect the fillers to form efficient conductive networks, which can not only reduce the amount of fillers, but also improve the electromagnetic shielding performance of the composites. Finally, this review put forward the development direction of polymer-based electromagnetic shielding materials in the future.