The effect of infliximab on gluconeogenesis in an animal model of diet-induced liver glucose overproduction was investigated. The mice were treated with standard diet (SD group) or high fat diet (HFD group). HFD group were randomly divided and treated either with saline (100 µl/dose, ip, twice a day) or infliximab (10 µg in 100 µl saline per dose, ip, twice a day, i.e., 0.5 mg/kg per day). SD group also received saline. The treatment with infliximab or saline started on the first day of the introduction of the HFD and was maintained during two weeks. After this period, the mice were fasted (15 h) and anesthetized. After laparotomy, blood was collected for glucose determination followed by liver perfusion in which L-alanine (5 mM) was used as gluconeogenic substrate. HFD group treated with saline showed higher (p < 0.05) liver glucose production from L-alanine and fasting hyperglycemia. However, these metabolic changes were prevented by infliximab treatment. Therefore, this study suggested that infliximab could prevent the glucose overproduction and hyperglycemia related with glucose intolerance and type 2 diabetes.