The invention provides a conductive ABS/PC composite material for 3D printing. The composite material is prepared from the following raw materials in percentage by mass: 15-30% of bulk process ABS, 15-30% emulsion method ABS, 1-5% of graphene nanoplatelets, 2-20% of a styrene-N-phenyl-maleimide-maleic anhydride terpolymer, 30-55% of polycarbonate and 0.5-5% of a multiwalled carbon nanotube. An ABS composite substrate with good compatibility is formed according to ABS in different size distribution. The composite material with a relatively good conductive performance is synthesized based on a less amount of the multiwalled carbon nanotube. The interlayer bonding property of the material is good, the surface layering phenomenon is extremely relieved, and the original dimensional precision can be better retained on the surface of the product.