Electroactive poly(3-amino-4-hydroxybenzoic acid) nanoparticles were synthesized using cyclic voltammetry and exhibited high electroactivity in 0.30 M Na 2 SO 4 solutions with pH values ranging from 1.0 to 12.0. This indicates that polymer has excellent electrochemical properties even in near-neutral and alkaline solutions compared to polyaniline. The anodic and cathodic peak currents of the polymer increase linearly with the square root of scan rate from 5 to 150 mV s 21 , indicating that the electrode reaction is controlled by a diffusion process. The structure of the polymer was investigated using UV-visible spectroscopy, Fourier transform infrared spectroscopy, proton nuclear magnetic resonance, and X-ray photoelectron spectroscopy. Based on the spectroscopic measurements, a possible polymerization mechanism of 3-amino-4-hydroxybenzoic acid was proposed. The polymer surface morphology was characterized by scanning electron microscopy. The enhanced electrochemical properties are ascribed to the synergistic effect of ACOOH and AOH groups in the polymer chains.