Polymers and their composites used in electrical memory devices have attracted much interest due to several advantages such as their low cost, easy processability and the possible development of three-dimensional stacking devices. In this chapter first we provide a short introduction to polymer composite-based electrical memory devices. Then we will discuss the up-to-date developments of polymer composite materials including polymer blends and multilayer hybrids for promising electrical switching behavior, mostly focusing on the role of these materials in memory functionality and the proposed mechanism.