Piezoresistive effect in polymer electrically conductive filler composites is highly dependent of filler concentrations, dispersion efficiency and filler geometry. Various carbon allotropes are one of the most commonly used fillers for manufacturing of these composites. In this paper we studied the influence of various carbon allotropes and concentrations on the piezoresistive properties of polyisoprene nanostructured carbon allotrope hybrid composites. Hybrid composites with various ratios and concentrations of multi wall carbon nanotubes and electrically conductive carbon blacks were made. The piezoresistive response of the composites have been determined under 1 atmosphere of external pressure in cyclic loading-unloading conditions. It has been observed, that hybrid composites with certain filler concentrations and ratios has significantly higher piezoresistive sensitivity compared to polyisoprene carbon nanotube composites and polyisoprene carbon black composites. Based on these results the impact of the carbon nanotube and carbon black concentrations on the polyisoprene nanostructured carbon allotrope hybrid composites piezoresistive properties is discussed.