The invention discloses an oil leakage-preventing oil pressure disc brake. The oil leakage-preventing oil pressure disc brake comprises a disc brake body. The upper portion and the lower portion of an inner cavity of the disc brake body are both provided with a brake pad. Bakelite pistons are arranged on the sides, away from each other, of the brake pads. Fixing rings are arranged between the bakelite pistons and the wall of the inner cavity of the disc brake body and are fixed to the wall of the inner cavity of the disc brake body. Rubber rings are arranged at the ends, away from the brake pads, of the bakelite pistons. The two ends of each rubber ring abut against the wall of the inner cavity of the disc brake body and the corresponding fixing ring respectively. By arranging the fixing rings between the bakelite pistons and the wall of the inner cavity of the disc brake body, the fixing rings abut against the rubber rings when the bakelite pistons and the rubber rings move at the same time, in this way, the rubber rings are prevented from being separated from the wall of the inner cavity of the disc brake body, and the oil leakage preventing effect is improved.