Epoxy resin sheets modified with titania (rutile) and silica on various concentrations up to 10% were investigated relative to the evolution of electrical resistivity and the modification of surface quality, when they are subjected to accelerated ageing in γ-radiation field. The changes in foreseen properties were qualified after receiving different γ-irradiation doses (0, 10, 20, and 50 kGy). The influence of irradiation environment degradative exposure to the high energy radiation was carried out in three environments (air and distilled water) for accomplishing comparative responses of material involving the contribution of radiolysis products of water.