The poor electrical conductivity of carbon foam limits its application as an electrode material. Thus, improving the electrical contact between carbon foam and other materials could greatly enhance its potential in the electrochemical field. Increasing electron transfer rates are crucial ways to improve the electrical conductivity of electrode materials. This research aims to modify the carbon foam electrode with gold nanoparticles and 4-mercaptobenzoic acid through a hydrothermal method and evaluate its conductivity through an electrochemical method. The modified electrode was characterized by using UV-Vis spectroscopy, XRD, FTIR, and SEM, which confirmed that the gold nanoparticles have adhered to the carbon foam surface and estimated to have a diameter around 50 nm. The electrochemical performance of the modified carbon foam was further evaluated in the three-electrode system through cyclic voltammetry analysis and the observed current density value was increased from 6.0611 mA·cm-2 to 11.8136 mA·cm-2.