The irreversible loss problem of surface enhanced Raman scattering(SERS) intensity, i.e. SERS intensity dependence on time, was studied in the 1M KCl/water/silver electrode SERS system. The SERS intensity of the O-H stretching vibrational band of surface water molecules was observed for over 90 minutes under the same external conditions to follow the time dependence of the SERS intensity after completion of the oxidation-reduction cycle. The SERS intensity was found to follow a time dependence of exp(-a/t) instead of the simple exponential decay of previous reports.