Nano- or microscale probes having high aspect ratios (A/Rs) are highly desired as biological sensors for single cell analysis or local disease detection of biological tissue. Although various top-down MEMS or bottom-up CVD growth technologies have been developed to fabricate high A/R nanoprobes, the complex fabrication process and requirement expensive equipment are less attractive. Thermal drawing, as a nanoscale rapid prototyping method, can fabricate polymeric nanoprobes with extremely high A/Rs within a few minutes on almost any surface under atmospheric condition. However, the non-conductive nature of polymeric nanoprobes is limiting the function as electrochemical sensor, which is essential for most biological sensing. In this work, we developed electrically-conducting MWCNT/SU-8 composite polymeric nanoprobes for electrochemical impedance measurement of biological tissue specimen. Since shear flow of polymer melt induced the align of MWCNT during thermal drawing, this alignment resulted in the increases of mechanical and electrical properties of the polymer composite. The effects of drawing conditions on the morphology of the composite nanoprobes were also studied and analyzed in terms of the mechanical and electrical properties. Their performance as impedance sensors were also characterized using tissue samples such as blood vessels or porcine skin.