Fabrication of conducting polymer networks based on polypyrrole/multi-walled carbon nanotubes (PPy/MWCNTs) modified graphite electrodes that were achieved with a single-step electropolymerization and potential use of these electrodes for deoxyribonucleic acid (DNA) recognition and anticancer drug (Paclitaxel, PTX) quantification were presented in the present work. PPy/MWCNTs nanohybrid PGEs were constructed in aqueous solution of pyrrole (Py) and MWCNTs using cyclic voltammetry (CV) and constant potential electrolysis. So-formed electrodes were characterized with cyclic voltammetry and electrochemical impedance spectroscopy (EIS). Surface morphologies of the surfaces were investigated by scanning electron microscopy (SEM) studies. Bio-application of the PPy/MWCNTs nanohybrid modified PGEs were accomplished by subjecting them to double-stranded DNA (dsDNA) modification for direct DNA recognition and PTX determination. For the drug determination, interaction of DNA-based electrodes with PTX was investigated. Detection limit was found as 1.55 x 10(-8) M based on the changes in the oxidation of guanine base which made the proposed electrode convenient for clinical trials.