Diets containing high levels of carbohydrate could inhibit the feeding in many fish species, but the relevant mechanisms of feeding regulation are not clear. The mandarin fish (Siniperca chuatsi), a typical carnivorous fish, exhibits an apparent anorexia due to its extensive intolerance to dietary carbohydrates, which limits the development of its culture industry. In this study, intracerebroventricular (ICV) injections of saline (control), 2-DG (glucose metabolism antagonist, 100 mg/kg) and glucose (10 mg/kg) were performed to investigate the impacts on feeding and glucose metabolism at 3 h, 6 h and 12 h in mandarin fish. The results showed that ICV of glucose significantly inhibited the feed intake of mandarin fish, while the plasma glucose levels remained constant at different time points. The mRNA levels of glucokinase (gk) were significantly induced at 6 h after ICV administration of glucose, indicating the presence of a glucose-sensing system in the hypothalamus of mandarin fish. ICV administration of glucose significantly promoted the mRNA levels of the cocaine- and amphetamine-regulated transcriptional peptide (cart) at 3 h and the inhibited the neuropeptide spiny mouse-associated protein (agrp2) at 12 h, which may be related to the significant upregulation of mTOR in the hypothalamus (12 h) and liver (6 h) of mandarin fish. In addition, ICV administration of glucose significantly induced the expression of gk (6 h) and pk (3 h) in the liver of mandarin fish to promote glycolysis, suggesting the promotion of catabolism for energy supply through perceived glucose levels in the hypothalamus. In conclusion, this study demonstrates for the first time that the hypothalamus gk can response to the glucose level, suggesting the potential existence of glucose sensing system in the hypothalamus of mandarin fish, and that ICV administration of glucose regulates the AMPK/mTOR pathway through gk-induced glucose sensing, which in turn regulates the expression of appetite-related genes to inhibit the feed intake. The present study would provide a theoretical basis for research on the carbohydrate utilization and feeding regulation in mandarin fish.