The emphasis in the present study was placed on developing Raman spectroscopy into a versatile technique, which offers intriguing opportunities for investigating electrocatalytic reaction. Through the in-situ Raman spectroscopic study, with a confocal Raman microscope, on the methanol electrooxidation on platinum electrodes with various surface roughness, it has shown the advantage in obtaining the informative spectra during the surface reaction with high faradaic current. This is hard to be performed by the other spectroscopic methods that have to use the thin-layer cell. The ability to obtain both the low frequency and the high frequency vibrations of Pt-C and C=O bands allows the assignment of surface species unambiguously. The ease of studying the surface bonding, investigating highly roughened surfaces with dark color and using high concentration electrolyte may provide a way to bridge the gap between the systems of fundamental research and practical applications. The results reveal the surface roughness effect on the electrooxidation process and provide clear evidence for the parallel oxidation mechanism. (C) 2000 Elsevier Science Ltd. All rights reserved.