A detailed surface Raman study of the effect of the bulk concentration of cyanide (CN-), electrode potential. and immersion potential on the adsorption behavior of CN- on the Pt electrode surface was performed on a confocal microprobe Raman system. The notable change of the C-N frequency and the Pt-C intensity at ca. -0.7 V (vs SCE) indicates a subtle change of the adsorption behavior of CN- on the platinum electrode in solutions with concentration of about 10(-4) M or lower. The concentration of cyanide in the bulk solution affects the adsorption behavior. The surface Raman signal can still be observed at concentrations as low as 10(-6) M. When the CN-concentration is higher than 10(-3) M, the potential for immersing the platinum electrode in the CN- solution has a remarkable effect on the adsorption behavior of CN-. With the high-quality surface Raman spectra, the surface enhancement factor for the adsorbed CN- was estimated to be about 150.