A simple, rapid, accurate, economical and reproducible spectrophotometric method for estimation of rabeprazole sodium (RAB) has been developed. The method employs estimation by straight line equation obtained from calibration curve of rabeprazole sodium. Analysis was performed at 284.0nm which is absorbance maximum of the said drug in 20% v/v aqueous methanol as solvent. The method obeys Beer’s law between 4.08 – 24.5 μg/. Results of analysis were validated statistically by ICH guidelines 1996.