Abstract: Metabolic syndrome (MetS) is a constellation of multiple metabolic risk factors including hypertension, dyslipidemia, glucose intolerance, insulin resistance and abdominal obesity. Over the past decades, the prevalence of MetS has increased dramatically, imposing a devastating and pandemic health threat. Pigment epithelium-derived factor (PEDF) is a multifunctional glycoprotein belonging to the superfamily of serine protease inhibitors produced from a variety of tissues. Cuulative studies have demonstrated that PEDF plays a pivotal role in the etiology of MetS. The present review focuses on the critical roles of PEDF in the development of MetS and the mechanisms behind them.