This invention provides an organic dispersion-type electroluminescence (abbreviated as "EL") element comprising a backing electrode, a reflective insulating layer, a luminescent layer, and a transparent electrode, wherein said reflective insulating layer comprises a high dielectric binder resin, an inorganic high dielectric material (i.e. powdery barium titanate), an impurity ion killer, and/or a hydrophobic hydrocarbon group-containing alkoxysilane compound, which is effective for inhibiting or preventing undesirable deterioration of dielectric properties and shortening of durability induced by the impurity ions present in the powdery barium titanate, and further a high dielectric graft polymer composition which is useful as a high dielectric binder resin used in the preparation of the reflective insulating layer and luminescent layer in said EL element. Said dispersion-type EL element has usually used as a back-lighting, for example, in liquid crystal display (LCD) element in word processing machines or note-type personal computer.