In previous studies we have reported that piezoresistive effect in polyisoprene electrically conductive filler composites is highly dependent on filler concentrations, dispersion efficiency and filler geometry. In this study polyisoprene nanostructured carbon allotrope hybrid composites have been elaborated using various ratios and concentrations of multiwall carbon nanotubes (outer diameter 50-80nm, length 0,5-2 μm, surface area 40 m2/g) and electrically extra conductive high structure carbon blacks (average particle diameter 30nmm, surface area 950 m2/g). The piezoresistive effects of the hybrid composites have been tested under 1 and 10 atmospheres of external pressure in cyclic loading/unloading regime using Zwick/Roell Z2.5 universal material testing machine, coupled and synchronized with Agilent A34970A digital multimeter/multiplexer. It has been observed, that composite with certain filler concentrations and ratios has a significantly higher piezoresistive sensitivity compared to polyisoprene carbon nanotube composites or polyisoprene carbon black composites. Based on these results the impact of the synenergy of both carbon nanotubes and carbon black at different concentrations on the polyisoprene nanostructured carbon allotrope hybrid composites piezoresistive properties have been evaluated and improved piezoresistive sensitivity is discussed.