The invention discloses a transmission project low sag wire. The wire comprises a center stress unit, a first aluminum conductive layer, a second aluminum conductive layer and a third aluminum conductive layer, wherein the first aluminum conductive layer, the second aluminum conductive layer and the third aluminum conductive layer are sequentially twisted on the outer surface of the stress unit. The stress unit comprises a first carbon fiber single line located at the center and six second carbon fiber single lines stranded on the outer surface of the first carbon fiber single line. A polyester adhesive filling part is formed by mixing a first component and a second component according to the mass ratio of 1: 2 to 4. The first component is composed of, by weight, N-307 unsaturated polyester, butyl acrylate, isooctyl acrylate, n-butanol, toluene, talcum powder, aluminum powder, calcium carbonate and triethylene tetramine. According to the invention, the transmission project low sag wire has the advantages of heat resistance, cold resistance, acid and alkali salt medium corrosion resistance, thermal stability, good fixability and high anti-slip property.