Abstract:The anti-oxidative and anti-inflammatory activities of high density lipoproteins (HDL) are largely due to the paraoxonase 1 (PON1) located on it. PON1 is mainly synthesized in the liver and secreted into the circulation, using very low density lipoprotein (VLDL) as a vehicle to bind with HDL, and transferred between in the HDL subclasses. PON1 possesses a higher activity through interacting with other protein components in HDL, and plays an important role for HDL structure and its anti-oxidative and anti-inflammatory activities. The change in quantity and activity of PON1 is associated with abnormal structure and the atherogenic “dysfunction” of HDL. In this review we summarize data on the role played by PON1 on HDL structure and function, focusing on the relationship between their binding and interaction and function of HDL.