Generic PD (Partial discharge) resistance characteristics of polymer nanocomposites are discussed mainly on thermosetting epoxy nanocomposites containing silica, alumina, titania, silicon carbide and layered silicate nano fillers. Generic PD erosion process comprises a process of erosion of epoxy to be impeded by nano fillers and interfaces. It is stressed that only epoxy regions can be eroded. Three-dimensional (3D) segmentation of epoxy by nano fillers is a dominant factor to increase PD resistance. When nano fillers are small in size, and interfacial thickness is large, increased PD resistance can be expected. The interfacial thickness is related to interaction zones. Addition of coupling agents will increase and tighten the interaction zones. Nano fillers tend to remain on the surface of nanocomposites under test. This performance will also help increase PD resistance.