Dissociative adsorption and oxidation of glycine on Au(111) single crystal electrodes in alkaline solutions were studied in the present paper using cyclic voltammetry (CV), in situ FTIR spectroscopy (FTIRS) and electrochemical quartz crystal microbalance (EQCM). In situ FTIRS results demonstrated that adsorbates derived from glycine dissociative adsorption are adsorbed cyanide anions (CN a d - ). The CN a d - species are stable on Au(111) surface in the potential region from -0.8 to 0.0V, and can be oxidized when electrode potential is increased above 0.1V. The oxidation of CN a d - releases surface active sites for further glycine oxidation. The products of CN a d - oxidation were determined by in situ FTIRS as cyanate (OCN - ), aurous cyanide (AuCN) and aurous di-cyanide (Au(CN) 2 - ). The formation of Au(CN) 2 - may initiate a dissolution of Au(111) surface atoms, which has been confirmed by a loss of surface mass determined in EQCM studies. It has revealed also that at high electrode potential region glycine may be split on Au(111) surface to form AuCH 2 NH 2 and AuCOO - adsorbates. Further oxidation of these species yielded CO 2 and -NH 2 , and the AuCH 2 NH 2 may be also combined with surface Au oxide to form methylamine. The CO 2 species produced in glycine oxidation are all retained in alkaline solutions to generate carbonate (CO 3 2 - ) and bicarbonate (HCO 3 - ) species that were clearly determined by in situ FTIRS studies.