The electrification phenomena of polymerized materials is governed by the competitive processes of the charge generation and the charge dissipation. In this paper, The charged particles were supplied on the naked upper surface of the polyethylene film from a point corona discharge with a screen electrode which controls the potential difference across the film. The charging current with the corona charging was found to be larger than that obtained with the electric charging on the MIM structure and the discharge current was found to flow in the same direction as that of the charging current. these results can suggest that the charge injection occurs from the interface between the polethylene surface and the accumulated charge layer, the injected charge are trapped and the space charge is established.