This study was undertaken to compare the effects of garlic (G) on hypercholesterolemic risk factors in rats fed with corn oil (C) or olive oil (O) with and without cholesterol (Ch) enrichment in the diet. Male Sprague-Dawley rats (n=6 per group) were fed semi-purified diets containing 5% oil with or without cholesterol (Ch) or garlic (G) for 21 days. In the C fed rats, addition of dietary Ch, there was a redistribution of Ch from HDL to LDL class. In contrast, 1% Ch added to O diets produced a 4-fold increase in serum Ch compared with levels in rats fed O without Ch. This was associated with a 14-fold increase in LDL Ch and a 7-fold decrease in HDL Ch levels. Addition of 2% G had no effect on the distribution of serum Ch between HDL and LDL Ch in C+Ch fed rats, but in O+Ch fed rats, G halved the increase in serum Ch and LDL and attenuated the decrease in serum HDL by 23%. The results suggest that the dietary O regulated the levels of serum in Ch loaded rats. G attenuated serum Ch in O fed rats and decreased serum risk factors, both total Ch and LDL-C ratio and LDL-Ch/HDL-Ch ratio.