-Context -Ulcer is the most common gastrointestinal disturbance resulting from an inadequate gastric mucosal defense.Several drugs are available in the market to address the disease; however, these drugs are associated with unnecessary side effects. Objectives -Previous research have confirmed the efficacy of plant extracts for possible treatment of the disease. This research aims to evaluate the anti-ulcer properties of medicinal plants. Methods -Methanol extracts from the leaves of Intsia bijuga, Cynometra ramiflora, Tamarindus indica, Cassia javanica, Cassia fistula, Bauhini purpurea, Senna spectabilis, Senna siamea and Saraca thaipingensis were evaluated for their anti-ulcer activity using HCl-ethanol as ulcerogen. Results -All extracts showed inhibitory activity with I. bijuga, T. indica, S. spectabilis and S. thaipingensis exhibiting more than 50% inhibition. S. thaipingensis showed the highest activity at 80%. S. spectabilis and S. thaipingensis were partitioned further into hexane, ethyl acetate and aqueous fractions. The aqueous and ethyl acetate fractions of S. spectabilis showed significant increased in its activity while the hexane and ethyl acetate fractions of S. thaipingensis gave higher activity than its aqueous portions. Conclusion -We conclude that plant extracts are potential sources of new anti-ulcer agents.