Squalene (SQ) and shark liver oil (SLO) are popularly sold as health supplements. The present study was designed to test the hypercholesterolemic activities of pure SQ and SLO in hamsters. SQ was supplemented in diets at the levels of 0.05, 0.1 and 0.5% while SLO was added in the diet at 0.05% by weight. When compared with the control group, serum total cholesterol (TC) was elevated by 32% in the 0.05%SQ group, by 23% in the 0.10%SQ group, by 35% in the 0.5%SQ group and by 19% in the 0.05%SLO group, respectively. The similar trend was observed for serum triglycerides (TG). SQ or SLO feeding also elevated hepatic cholesterol by 97-133% in the four tested groups compared with the control hamsters. In addition, supplementations of SQ and SLO in diets caused significant accumulation of SQ in the liver and adipose tissue. The present results suggest that SQ and SLO are hypercholesterolemic at least in hamsters. Caution has to be taken when SQ or SLO are routinely consumed as health supplements.