Abstract: This invention discloses a dielectric pipe flange gasket having the dual functions of providing a leak proof seal for the pipe flange joint and an electrically insulating barrier between flanges, which dielectric pipe flange gasket comprises a planar annular disc member of corrosion resisting metal sandwiched between two hard dielectric planar members respectively bonded to two faces thereof and a pair of ring seals made of dielectric elastomer respectively disposed in two annular seal grooves respectively included in two faces of the pipe flange gasket, wherein the depth of the grooves partially extend into the metallic planar annular disc member.