In this paper the use of a novel TEMPO-based transition metal free homogeneous catalyst system, TEMPO/NaNO2/NH4Br/1,1,3,3-tetramethylguanidine sulfonic acid, for the aerobic oxidation of various alcohols to the corresponding aldehydes and ketones is described. The reactions are carried out in aqueous acetonitrile under atmospheric pressure and ambient temperature. The catalytic system exhibits excellent activity for the selective aerobic oxidation of alcohols.