The invention discloses an antistatic flame-retardant composite material for coal mines and a preparation method of the antistatic flame-retardant composite material. The antistatic flame-retardant composite material comprises the following components in parts by weight: 100 parts of polyvinyl chloride (PVC) resin, 5-20 parts of acrylonitrile-butadiene-styrene copolymer (ABS), 2-10 parts of compatibilizer, 0.5-2 parts of carbon nano-tubes, 0.5-2 parts of graphene, 2-6 parts of thermal stabilizer, 1-2 parts of lubricant and 2-10 parts of processing aid. The preparation method comprises the following steps: preparing a conducting filler/PVC composite powder material from a mixture of the carbon nano-tubes and the graphene and part of the PVC resin in proportion; performing high-speed mixing on the obtained conducting filler/PVC composite powder material, the residual PVC resin, the ABS, the compatibilizer, the thermal stabilizer, the lubricant and the processing aid to obtain a compound; and putting the mixed compound into a conical twin-screw extruder, setting temperature section by section, and pelleting by extruding, thereby obtaining the antistatic flame-retardant composite material for the coal mines. The prepared PVC composite material has relatively high mechanical properties, excellent antistatic property and flame retardance, is a high-polymer composite material with good processibility, and can be used underground in the coal mines.