In this letter, the dielectric properties of the untreated multiwall carbon-nanotubes/poly(vinylidene fluoride) (MWNT/PVDF) composites are studied. Towards low frequencies, the dielectric constant of a composite with about 2.0 vol % of MWNT increases rapidly and the value of the dielectric constant is as high as 300. However, by a calculation, the percolation threshold of the MWNT/PVDF composites is only 1.61 vol % (0.0161 volume fraction) of MWNT. Both the large aspect ratio and the high conductivity of the MWNT may lead to the low percolation threshold of the MWNT/PVDF composites. For the percolation composite, the dielectric loss value is always less than 0.4, irrespective of the frequency. Therefore, the experimental results suggest that the dielectric properties of MWNT/PVDF composites may be improved significantly without the chemical functionalization to carbon nanotubes.