Rh-catalyzed decomposition of ethanol into CO2 and CH4 via C-C bond splitting is reported in room-temperature liquid phase under atmospheric pressure. Mechanistic investigations show that C-C bond splitting of ethanol on the noble metal surface is rapid, and CO2 forms through the oxidation of alpha-CHxO and beta-CHx fragments after C-C bond splitting, while CH4 forms through the hydrogenation of beta-CHx utilizing H atoms from -OH, beta-CHx, and alpha-CHxOH fragments.