The invention discloses a +/-660 kV direct-current composite insulator which comprises an annular metal connecting piece located at the end, a sealing ring, an epoxy resin glass fiber stick, a sheath and grading rings. The annular metal connecting piece is connected with the grading ring at the grounding end. The grading ring at the grounding end is connected with the front end of the epoxy resin glass fiber stick through the sealing ring. The outer surface of the epoxy resin glass fiber stick is wrapped by the sheath. Umbrella skirts of three specifications are arranged on the sheath. The tail end of the epoxy resin glass fiber stick is connected with the grading ring at the high-voltage end. According to the +/-660 kV direct-current composite insulator, the structural mode of one large umbrella and two small umbrellas of an extra-large umbrella with arranged flowers is adopted, the creepage distance is effectively increased on the basis of an existing structural height, the electric field distribution of the surface of the +/-660 kV direct-current composite insulator is improved, the local field intensity is reduced, partial discharge is restrained, meanwhile, ice and snow bridge connection can be blocked due to the structure, and the +/-660 kV direct-current composite insulator has the good ice, snow and lightning prevention capacity.