We investigated the possible effect of apolipoprotein E (apo E) polymorphism on hypertriglyceridemia in type II diabetes mellitus (DM) patients by both apo E genotyping and phenotyping methods.Eighty Korean type II DM patients were evaluated. Restriction isotyping after DNA amplification was used for apo E genotyping. The isoelectric focusing of neuraminidase-treated sera followed by immunoblotting was used for apo E phenotyping.The concordant rate between apo E genotyping and phenotyping was 96.3%. Apo E genotype frequencies for all 77 concordant cases were as follows: 72.7% for epsilon 3/3; 16.9% for epsilon 3/4; 7.8% for epsilon 2/3; 1.3% for epsilon 2/4, 1.3% for epsilon 4/4; and 0% for epsilon 2/2. There were no significant differences in apo E genotype frequencies between hypertriglyceridemic (n = 42) and normotriglyceridemic (n = 35) groups.Our findings could not support the association between apo E polymorphism and hypertriglyceridemia among type II DM patients.