The invention discloses a PVC foam wood / plastic composite material and relates to the technical field of composite materials. The PVC foam wood / plastic composite material is made from the following raw materials in parts by weight: 20-70 parts of PVC resin powder, 0-55 parts of wood flour, 5-40 parts of calcium carbonate powder, 0.1-0.5 part of sodium bicarbonate, 0.3-0.6 part of an azo-compound or hydrazine derivative, semicarbazide compound or nitroso-compound, 2-10 parts of a foaming regulator, 1.5-6 parts of a composite stabilizer, 0.7-2.1 parts of a lubricant, 0.5-1.2 part of soybean oil, 2.5-5.5 parts of an impact modifier, and 0.5-3 parts of a processing agent. The PVC foam wood / plastic composite material provided by the invention has the advantages of strong chemical stability, high strength, resistance to acid / alkaline corrosion, resistance to water seepage, flame retardancy and low cost.