Abstract: The multiwalled carbon nanotubes/polystyrene-polyvinyl chloride (MWNTs/PS-PVC) composites were prepared by solution blending, and the electrical property of composites was studied. Through the measurement of concentration of carriers, the mobility and the calculated conductivity activation energy, the influence factors on the composite material conductivity and the electrical conductivity mechanism of MWNTs/PS-PVC composites were analyzed. The results show that when the mass ratio of PS/PVC is 1:1, the sample is found which exhibits the lowest electrical percolation threshold in all the composites. MWNTs/PS-PVC composites with 1.5% mass fraction of MWNTs, the electrical property of the samples changes with the content of PS, the electrical conductivity of the samples containing 50% PS in PS-PVC is improved by 4 orders of magnitude compared with that of MWNTs/PVC composites. During the formation of conductive network, the n-i-p-i alternating structural units in the composite are similar to the super lattice structure of the inorganic compound, reducing the conductivity activation energy and increasing the carrier concentration, which causes the electrical conductivity of MWNTs/PS-PVC composites to improve significantly.