The fabrication of an electrochemical sensor based on polypyrrole-Pd nanocomposites modified gold electrode (PPy-Pd-AuE) and its electrodetection of ascorbic acid is described. The PPy-Pd nanocomposites were synthesized by chemical method and characterized by different techniques. The Pd nanoparticles incorporated with PPy were confirmed by x-ray diffraction, scanning electron microscope, elemental dispersive spectroscopy and transmission electron microscopy analysis. The electrochemical behavior of polypyrrole-Pd nanocomposites towards the electro catalytic oxidation of ascorbic acid was investigated by cyclic voltammetry, differential pulse voltammetry and square wave voltammetry. The observed cyclic voltammetry, differential pulse voltammetry and square wave voltammetry response depended linearly on concentration of ascorbic acid in the range of 100-1000 mM with correlation coefficients of R 2 =0.977, R 2 =0.980, R 2 = 0.990 and sensitivity 7.96 mA/mM.cm 2 , 0.70 mA/mM.cm 2 and 2.10 mA/mM.cm 2 respectively. The reproducibility of PPy-Pd-AuE electrode from CV, DPV and SWV were found to be 3.9%, 4.69% and 2.98 % respectively. These results indicate the PPy-Pd-AuE exhibited excellent platform and could be used for electrochemical determination of ascorbic acid.