Electrical conductive polymer nanocomposites have been used in a wide range of technological applications, such as sensor, anti-statics, microwave absorbing, and conductive coating. In general, for all this applications it is desired the using of low fillers concentrations to get conductivity and good processability. In this work the rheological and the electrical percolation thresholds of multi-walled carbon nanotubes (MWCNTs) in three different polymer matrix were studied and compared. Nanocomposites of polystyrene (PS)/MWCNT, poly(vinylidene fluoride) (PVDF)/MWCNT and polystyrene-b-polybutadiene-b-polystyrene (SBS)/ MWCNT were produced by melt mixing using an internal mixer. MWCNT contents between 0 and 5% (v/v) were chosen for the study. The rheological percolation was characterized by oscillatory rheometric measurements monitoring the storage modulus (G’()) and loss modulus (G”()) as function of the oscillatory frequency. The electrical percolation was characterized by impedance spectroscopy monitoring the electrical conductivity as function of the frequency of electric field. The results showed that for PS the rheological and electrical percolation thresholds were both around 3.5 (v/v) respectively. But, for PVDF this thresholds were reduced for 1.1 and 0.8, respectively, and, for SBS this thresholds were reduced for 0.7 and 1.3, respectively. This differences could be attributed to the differences between the polymer matrices. PS, PVDF and SBS are all non-polar matrices, but PS has only one phase and PVDF and SBS has two phases. PVDF is a semicrystalinne polymer with ~48% of crystallinity. SBS is a block copolymer with 40%(v/v) of PS phase. The presence of a second phase, probably acted reducing the free volume and making both percolations easier.