Three restriction fragment length polymorphisms (RFLPs), EcoRI (R), Xbal (X), and Mspl (M) of the apolipoprotein (apo)B gene, were studied to determine their distribution frequencies and influence on the lipid profiles in 148 Chinese patients with documented coronary heart disease (CHD) and in 153 healthy subjects. The plasma concentrations of cholesterol and apoB showed no difference between the CHD patients and controls. However, CHD patients had significantly higher concentrations of low-density lipoprotein cholesterol and triglyceride and lower concentrations of high-density lipoprotein cholesterol than the controls. The frequencies of these three apoB RFLPs did not differ between the CHD patients and controls. Compared with South Asians and Caucasians, the Chinese in Taiwan showed a much lower frequency of R-, X+, and M- alleles. There was no evidence of an association between lipid profiles and RFLPs in either CHD patients or controls. The weak association of EcoRI, Xbal, and Mspl polymorphisms of the apoB gene with CHD indicates that the three RFLPs cannot be used as a predictor for the risk of CHD in the Chinese population.