Gastric ulcer is a serious condition that results from the wearing/tearing of the stomach mucosa. A physiological equilibrium is maintained between mucosal defense and aggressive factors. In this study, the effectiveness of medicinal plants (Hypericum perforatum) in the management of gastric ulcer was compared to that of omeprazole, a well-known drug for gastric ulcer. This study involved numerous study groups of male rats comprising of the following: the first group (control group exposed to H. pylori and fed with normal animal feed), the second group (rats exposed to H. pylori and treated with two doses {of 250 mg/kg and 500 mg/kg} of aqueous H. perforatum), and the third group (rats exposed to H. pylori and treated with 20 mg/kg of omeprazole). The outcome of the study demonstrated that a high dose of H. perforatum prevents (50.65%) the development of stomach ulcers. The group treated with omeprazole revealed a formation of stomach ulcers (24.50%). A high dose of the aqueous plant extracts showed greater effectiveness in preventing gastric ulcer formation compared to the lower dosage.