To achieve coordination programming at an electrode surface, the first functional layer is highly important. In this study, high-resolution electron energy-loss spectroscopy (HREELS) was used to investigate coronene monolayer adsorption on a Au(111) substrate at 300 K. In the spectra, only a band attributable to the out-of-plane vibration mode was observed, suggesting that coronene molecules adsorb on the substrate with a flat orientation. Furthermore, the HREEL spectra showed that the coronene monolayer was stable even after heating to 400 K.