The present investigation was performed in pylorus ligation-induced ulcer model in wistar albino rats in which ability of different extract o f Plectranthus amboinicus (Lour) was tested in at dose level of 200mg/kg body weight orally and co mpared with Ranitidine (30mg/kg) as standard. From the results it is concluded that the various extract of Plectranthus amboinicus (Lour) (200mg/kg) showed highly significant anti-ul cer activity.