Plasma cholesteryl ester transfer protein facilitates the transfer of cholesteryl ester from HDL to apolipoprotein B-containing lipoproteins. Its significance in atherosclerosis has been debated in studies of human population genetics and transgenic mice. The current review will focus on human plasma cholesteryl ester transfer protein research, including TaqIB, 1405V, and D442G polymorphisms. Plasma cholesteryl ester transfer protein has a dual effect on atherosclerosis, depending on the metabolic background. In hypercholesterolaemia or combined hyperlipidaemia, plasma cholesteryl ester transfer protein may be pro-atherogenic and could be a therapeutic target.