Abstract: A preliminary study of oxide on the surface of glassy carbon electrode by the use of in-situ infrared reflection spectroelectrochemical method has been done. In the electrochemical polarization of carbon electrode by high anodic potential(>1.6 V vs. SCE), the formation of adsorbed carbon monooxide, microcrystal graphite, as well as other oxide species on the surface of carbon electrode can be detected. Ester and acid anhydride are proposed to be two main oxide species being produced on the surface of glassy carbon electrode.