Obesity induced by high-fat (HF) feeding is associated with low-grade inflammation in peripheral tissues that predisposes to insulin resistance. Recent evidence suggests the occurrence of a similar process in the hypothalamus, which favors weight gain through impairment of leptin and insulin signaling. In addition to its implications for obesity pathogenesis, this hypothesis suggests that centrally targeted antiinflammatory therapies may prove effective in prevention and treatment of this disorder. This article highlights molecular and cellular mechanisms by which hypothalamic inflammation predisposes to diet-induced obesity.