Ghrelin O-acyltransferase (GOAT) is an enzyme specifically responsible for the octanoylation of the growth hormone secretagogue, ghrelin, a modification essential for ghrelin's biological activity. GOAT is primarily expressed in the epithelial cells of the stomach and small intestine and is located on the membrane of the endoplasmic reticulum. By catalyzing the octanoylation of ghrelin, GOAT influences physiological processes such as appetite regulation, energy balance, and insulin secretion. Its activity and expression are regulated by various factors, including nutritional status and hormone levels. The specific expression patterns and potential mutations of the GOAT gene are associated with the development and progression of metabolic diseases, such as obesity, metabolic syndrome, and diabetes. Researching GOAT and its interaction with ghrelin provides new perspectives for understanding and treating these diseases.