The role of lipoprotein lipase (LPL) in the development of atheromatosis is subject of the increased interest for about 20 years, since then Zilversmit observed that LPL activity is found in greater amounts in atherosclerotic than normal arteries. The general action of this enzyme is hydrolysis of triglycerides in triglyceride rich lipoproteins and thus regulation of metabolism of circulating as well antiatherogenic as proatherogenic lipoproteins. The effect of LPL on the biology of arterial wall seems to be atherogenic. The mechanisms of this effect of LPL is 1) augmentation of the adhesion and aggregation of LDL; 2) influence on the oxygen modification of LDL and increased uptake of oxy-LDL by macrophages; 3) dysfunction of endothelial barrier and retention of atherogenic lipoproteins in the arterial wall and 4) the activity of LPL macrophage origin. Possible atherogenic actions of LPL based on in vitro experimental studies are reviewed.