A systematic electrical and mechanical study was carried out on styrene butadiene rubber (SBR), as a nonpolar rubber, and nitrile rubber (NBR), as a polar one blended with pure and waste polyethylene (PE), low and high density. The compatibility investigations, which were carried out by the dielectric method and confirmed by the calculated heat of mixing, indicate that SBR-PE blends (either low or high density) are compatible, while NBR-PE blends are incompatible. From the electrical and mechanical results, it is found that the addition of waste PE to either polar or nonpolar rubber leads to better electrical and mechanical properties when compared with those for the blends having pure PE. The values of permittivity epsilon＇ are found to increase pronouncely, while the values of dielectric loss epsilon " slightly decrease. Shore hardness was also measured for all the investigated systems and found to vary linearly with the permittivity epsilon＇.