The invention relates to the field of sealing, in particular to a rubber sleeve with a lower end seal ring covered with an opened copper sheet, a packer and a bridge plug, wherein the rubber sleeve is used in the oil exploitation industry and can bearing high temperature and high pressure. The lower end seal ring of the rubber sleeve is covered with the first copper sheet, the first copper sheet covers the upper surface, the lower surface, the inner side face and the outer side face of the lower end seal ring, and the thickness of the first copper sheet is set in the mode that when the upper end bears first axial pressure, the lower end seal ring deforms in the radial direction so that the part, distributed on the inner surface of the lower end seal ring, of the first copper sheet can butt against a center tube and the part, distributed on the outer surface of the lower end seal ring, of the first copper sheet can butt against the sleeve; an annular opening is formed in the edge, located on the upper surface of the lower end seal ring, of the first copper sheet. The lower end seal ring is covered with the first copper sheet, the degradation function on the rubber sleeve by high-temperature and high-pressure steam micromolecules is reduced or prevented, and the sealing long-term effect of the rubber sleeve is improved.