Aim To investigate the relationships between -75 bp / +83 bp polymorphism in apolipoprotein(apo)A1 gene, lipids levels and the occurrence of coronary atherosclerosis disease(CAD). Methods The distributions of two MspI polymorphisms of the apo A1 gene, -75 bp and +83 bp, and blood lipids levels were determined among 137 Chinese patients in relation to circulating lipids and coronary angiography. Results The control group had higher M 1-/M 2- frequencies than the coronary atherosclerosis disease group (M 1: p<0.005; M 2: p<0.05) and the M 1- and M 2- alleles were associated with increased high density lipoprotein (M 1-: p<0.0001; M 2-: p<0.05) and apo A1 (M 1-: p<0.0001; M 2-: p<0.05) levels. M 1- and M 2- were significantly correlated with CAD (p<0.01 and p<0.05, respectively). Conclusions The results suggest that the base changes from G to A at the -75 bp site and C to T/G to A at the +83 bp site do have increased circulating levels of apo A1 and high density lipoprotein and that individuals with these base changes are likely to have a reduced risk of developing CAD.