Abstract Organic compounds with potential antioxidant activity have attracted special attention of researchers and they have been widely studied in several areas, including pharmacology and medicinal chemistry. In this context, electrochemistry through cyclic voltammetry becomes a fast and efficient tool for the characterization of the antioxidant potential of these compounds. Herein, a study was carried out on the electrochemical behavior of seleno‐dihydropyrimidinones and chloro‐dihydropyrimidinones via cyclic voltammetry in the presence of acetonitrile. By employing this approach, the characterization of the oxidation processes and the determination of antioxidant activities of the target molecules was disclosed. It was also proposed a comparison of the results obtained with the antioxidant activity of the 2,2‐diphenyl‐1‐picrylhydrazyl radical. Among the evaluated compounds, four molecules exhibited significant antioxidant capacities which were efficiently detected by 2,2‐diphenyl‐1‐picrylhydrazyl radical assay and by cyclic voltammetry when measuring the charges transferred until 0.9 V vs Fc + /Fc.