Effects of nifedipine and cimetidine on gastric acidity were studied in pylorus ligated rats in doses of 0.25 mg, 0.5 mg and 1.0 mg per kg given intraperitoneally (l/p). Both the drugs inhibited gastric secretions in a dose dependent fashion. Nifedipine was found to be slightly more effective than cimetidine in raising gastric pH and reducing acidity titratable to 7.0 pH at all doses. However, it was less effective in reducing volume of gastric secretions. It is likely that nifedipine has greater anti-ulcer effect than cimetidine in rats.