In this thesis, the electrochemical properties of gallic acid in different buffers and real samples were investigated using differential pulse voltammetry. The pH values of the buffers ranged from pH = 3.0 to pH = 9.5. The aim of this study was to investigate the influence of pH value on the potential of oxidation current peak of gallic acid, to investigate the influence of gallic acid concentration and rate of electrode polarization change on oxido-reduction properties of gallic acid, to investigate possible adsorption of the oxidation product of gallic acid on the surface of the working electrode and determine the gallic acid in real samples. Electrochemical measurements were performed in a three-electrode electrochemical cell where gold, platinum and glassy carbon electrodes were used as working electrodes, Ag / AgCl electrode was used as a reference electrode, and platinum wire was used as a counter electrode. It was found that gallic acid is oxidized under these experimental conditions, where two oxidation current peaks were detected, and its oxidation product was adsorbed on the electrode surface. The height of the oxidation current peak of gallic acid varied with the change of pH value, while the optimal pH value for its oxidation was around pH = 6.0. It was found that the oxidation current peak of gallic acid increases with increasing concentration (linear dependence in the range from 0.1 μmol dm-3 to 66.6 μmol dm-3). Gallic acid was detected in real samples in which its concentration varied from 0.4 μmol dm-3 till 35.6 μmol dm-3.