Nutritional intake is closely linked to gonadal development, although the mechanisms by which food intake affects gonadal development are not fully understood. Cholecystokinin (CCK) is a satiety neuropeptide derived from the hypothalamus, and the present study observed that hypothalamic CCK expression is significantly influenced by food intake, which is mediated through blood glucose levels. Interestingly, CCK and its receptors were observed to exhibit a high expression in the hypothalamus-pituitary-gonad (HPG) axis of grass carp (