The studies of electrical properties of the polyisoprene (PI) matrix/high structure carbon black (HSCB) composites (PCBC) with various concentrations (8, 9, 10 and 11 mass parts) of filler have been carried out in the temperature interval of 90K–330K. In this paper we focus on the investigation of direct current (DC) conductivity in a low-temperature region with negative temperature coefficient of resistivity (NTCR). It has been proven that variable range hopping (VRH) conduction is dominated by hopping of carriers among localized states in a low-temperature range. At higher temperatures the nearest neighbour hopping (NNH) conductivity or constant range hopping charge transport takes place. The reversibility as well as small hysteresis of resistance change versus temperature indicates prospective temperature sensor application for PCBC.