Materials for practical smart sensor applications are attracting serious interest over last few years. The major problem of conventional rigid sensor materials are difficulty to integer them into soft flexible structures. Polyisoprene/nanostructured carbon composite appears as promising materials for such application. Previous research approved nanostructured carbon black filled composites as finger pressure sensitive piezoresistive materials [1]. The change of tunneling currents between carbon aggregates causes rapid change of composite electrical conductivity under applied external load. Thus current phenomena can only be achieved if high structure carbon blacks (DBP apsorption is 380ml/100g) are used as conductive filler. Single and multi wall carbon nanotubes (CNT) originate with variable length to width ratio and high electric conductivity in longitudinal direction of tube. The specific properties mentioned above should make it possible to obtain electric percolation in polymer-CNT composites at very low loads of filler. However our recent experience [2] shows quite high value of percolation threshold but still good sensing properties in the vicinity of percolation region, if the CNT has been dispersed by “roll in” method. In this work an attempt to reduce percolation threshold of polyisoprene/multiwall CNT composite by sonicated and stirred dispersion of CNT in chloroform solution is presented. The percolation threshold and the excellent piezoresistive behavior of polyisoprene/multiwall CNT composite have been determined as well.