The invention discloses a novel composite conductive agent, a lithium ion positive pole piece and a lithium ion negative pole piece made of the composite conductive agent, and a lithium ion battery containing the positive pole piece and the negative pole piece. By leading the novel composite conductive agent, the developed pole piece of which the surface has an effective conductive network can be prepared by adding a small amount of conductive agent, so that the prepared lithium ion has excellent rate discharging, low-temperature discharging, high-temperature storage and cyclic properties. The composite conductive agent comprises single-wall or fewer-wall carbon nanotubes and graphene nanosheets, wherein the specific surface area of each single-wall or fewer-wall carbon nanotube is 200 to 1500m<2> / g, the tube diameter is 1 to 10nm, and the tube length is greater than 5mu m; the diameter of each graphene nanosheet is 0.2 to 2mu m, the specific surface area is smaller than 1800m<2> / g, and the thickness is smaller than 2nm.