Abstract: Gastric ulcer is one of the most prevalent gastrointestinal disorders and still remains a major on-going health concern. Phosphodiesterase V inhibitors (PDE V) are drugs currently used in the treatment of patients with erectile dysfunction and pulmonary hypertension. They act by increasing blood flow to tissues in response to increased cGMP levels. They are also Nitric Oxide (NO) donors. NO is a potent vasodilator which increases blood flow in tissues where present thus preventing tissue damage. This study therefore examined the effects Tadalafil (TAD) on Indomethacin-induced gastric ulceration in rats. Three studies were directed at examining the effects of Tadalafil on gastric ulceration, ulcer dimensions and histological profile in indomethacin-induced rats. Male Wistar Albino rats weighing between 180-220 g were used. Each experimental group containing 6 rats were divided based on the following pre-treatments: Group I (Control)-saline (8 mL kg^-1), Group II-IV were pre-treated with graded doses of Tadalafil (2, 5 and 10 mg kg^-1 body weight, respectively), Group V (Reference)-Cimetidine 100 mg kg^-1. Ulcer was induced by administration of indomethacin (40 mg kg^-1 p.o) 30 min following pre-treatments. Results showed that Tadalafil significantly reduced Indomethacin-induced gastric ulcers when compared with the control group (p<0.05) at high doses. The ulcer area, depth and width were significantly different between the control group and the Tadalafil 10 mg kg^-1 BW group. Tadalafil had ulcer-reducing effects similar to that of the reference drug, cimetidine. Similar pattern of dose-dependent attenuation of ulcer severity was observed in the histological study. This study provides evidence that Tadalafil possesses significant anti-gastric ulcer effects as it dose-dependently reduced gastric ulcers induced by Indomethacin in rats.