The invention relates to a one-component RTM (Resin Transfer Molding) anti-aging epoxy resin composition which comprises the following components in parts by weight: 100 parts of compound epoxy resin, 90-150 parts of a microcapsule-type curing agent, 0.5-5 parts of a compound light stabilizer and 1-10 parts of a diluent, wherein the microcapsule-type curing agent is composed of a capsule core and a capsule shell at the mass ratio of 1: (2-3), and the capsule core contains 80-95 percent by mass of a compound curing agent and 5-20 percent by mass of a compound antioxidant. The invention further protects molding epoxy resin prepared by taking the composition as a raw material.