The application discloses a composite material for the non-excavation improvement of a double-layer oil tank. The composite material comprises a double-layer oil tank high-barrier composite film and a frame cut-through layer. The double-layer oil tank high-barrier composite film comprises an oil-gas high-barrier layer and a static conductive layer. The frame cut-through layer is located on one side, opposite to the static conductive layer, of the oil-gas high-barrier layer. Base materials of the static conductive layer and the frame cut-through layer adopt a resin material or a modified oil-resistant plastic material. The frame cut-through layer is internally provided with a plurality of frames and communication chambers located between the frames for the arrangement of oil-gas leak detection components. The oil-gas high-barrier layer is made from an ethanol-gasoline barrier material. The present ethanol-gasoline barrier material is adopted for manufacturing the oil-gas high-barrier layer, thereby greatly improving oil gas barrier properties of the composite material to oil and gas. The phenomenon that the large-area corrosive leakage of oil tanks is much more likely to happen in districts selling ethanol gasoline is prevented, and the serious pollution to underground water and soil is avoided.