The effect of different doses of methanol extract of Terminalia avicennioides (Combretaceae) on acute mucosal damage induced by 0.6 M HCl and on mucus production in the stomach of rats was studied. Animals treated with T. avicennioides at a dose of 350 mg/kg showed a significant (P< 0.05) reduction of gastric lesions produced by HCl, while the reduction in gastric damage was highly significant (P< 0.01) at doses of 500 and 900 mg/kg when all the experiments were compared with rats treated with normal saline (untreated control). Similarly, the extract of T. avicennioides at 350, 500 and 900 mg/kg produced a significant (P< 0.05) increase in mucus production when compared with normal saline (untreated) and cimetidine (treated) control rats. The effect of the extract on both gastric damage and mucus production were shown to dose-dependent. This study has therefore validated the claim that the plant possesses an ulcer healing effect.