Abstract: The effects of long-term feeding of lipid-based diet (containing 5 and 10% cholesterol) on some lipid-metabolizing enzymes were examined by determining the activities of Lecithin: Cholesterol Acyl Transferase (LCAT), lipoprotein lipase (LPL) and triglyceride lipase (TGL). The LCAT activity was found to increase significantly (p< 0.05) in the cholesterol fed rats when compared to control animals fed the control diet and the increase was found to be dose dependent. The cholesterol fed rats also showed relatively significant (p< 0.05) increases in the levels of both cholesterol ester and free cholesterol. Similarly, both LPL and TG lipase activities were also significantly (p< 0.05) elevated in the cholesterol fed rats when compared to control. Histochemical evaluation of the liver of the rats fed 10% cholesterol at the end of the feeding period revealed chronic venous congestion and fatty changes. The kidney showed fat embolism with glomerular capillaries distended with fat globules. The aorta lumen was reduced to less than half the normal diameter by a greatly thickened intima which contained cholesterol crystals, typical of artheromatous plague. The implications of these findings are discussed with respect to artherogenesis, hyperlipoproteinemia and hypertriglyceridemia.