AIM: Fundectomy, shown as an alternative to restrictive techniques, causes absorption restriction and metabolic changes. This study aimed to examine the histopathological changes caused by the fundectomy as a technique applied to rats by hormones that affect stomach and obesity metabolism and its effect on weight loss. MATERIAL AND METHODS: 2randomly selected Winstar-Hannover rat groups were evaluated by measuring their pre-and postoperative weights and biochemically measuring Gastrin, Ghrelin, and Leptin levels on day 30. After sacrification, the stomachs were taken for histopathological examination. RESULTS: Significant weight loss was observed in the fundectomy group in the 1stmonth postoperatively. Biochemically, Gastrin means in the fundectomy group were statistically significantly higher than in the control group. The mean Ghrelin and Leptin levels of the Fundectomy Group were statistically significantly lower (p=0.005). Immunohistochemically, Gastrin means ™at the antrum and proximal stomach parts of the Fundectomy Group were significantly higher than in the control group. As Ghrelin, a significant decrease was observed in all 3regions of the Fundectomy Group compared to the control group. Leptin results were significantly lower at the antrum and proximal stomach parts of the Fundectomy Group. Histopathologically, in the Fundectomy Group, cystic glandular hyperplasia was moderate at the proximal stomach, foveolar hyperplasia was mild at the antrum, fibrosis was moderate at the antrum and corpus, and high at the proximal stomach. CONCLUSION: Fundectomy is an effective method in terms of weight loss. This animal experiment, conducted as a pilot study, will be an essential step in elucidating metabolic and histopathological changes. KEY WORDS: Bariatric surgery, Fundectomy, Obesity.