The present invention relates to the field of packaging materials, and discloses a plastic composition for packaging and an application thereof. The plastic composition contains epoxy resin having specific type and proportion, a curing agent, silicon micropowder, an imidazole curing accelerator, a mold release agent, a silane coupling agent, and a toughening agent, wherein, the epoxy resin comprises liquid crystal epoxy resin, glycidyl amine epoxy resin, o-cresol formaldehyde epoxy resin and biphenyl epoxy resin, wherein the curing agent is melamine modified novolac phenolic resin. The invention also discloses an application of the composition in preparation of the plastic used for package of an integrated circuit. Through cooperation usage of the specific epoxy resin, the curing agent, the filler, the auxiliary agent and the like, the plastic used for packaging with better performance is obtained, can be used for packaging the large-scale integrated circuit, and has advantage of environmental protection.