Aim : To clarify the role of ghrelin in the regulation of gastric acid secretion in both normal and experimental diabetic rats.Material and Methods : A total number of 140 adult male albino rats were included in this study. All animals were fed the same type of food to avoid the effect of diet on the experiments.. They had free access to water and kept at room temperature. The animals were divided into two main groups: Group A (Normal rats) , Group B (Streptozotocin –induced diabetic rats) . Each group was subdivided into four subgroups : Subgroup 1 : control group : injected with saline 0.5 ml i.v. in the tail vein ,Subgroup 2 : injected with Ghrelin 20µg /Kg i.v. ,Subgroup 3 : injected with Ghrelin 20µg /Kg i.v. + L-NAME 70 mg /Kg s.c.,Subgroup 4 : injected with L-NAME 70 mg /Kg ,Gastric secretions were collected and gastric secretion volume , both free and total acidity, pH were measured.Results :The study reported that ghrelin significantly enhanced the secretion of both gastric acid and mucus in both normal and diabetic rats,and these effects inhibited by the nitric oxide synthase inhibitor, L_NAME. Also, there was a significant reduction in gastric acid secretion in STZ – induced diabetic rats in comparison with that in normal rats.Conclusions : Ghrelin plays a stimulatory role on gastric acid secretion and mucus secretion in both normal and STZ-induced diabetic rats and the nitric oxide synthase inhibitor L-NAME blocks this effect. So, this role is performed via nitric oxide as a mediator.