A study on LDL receptors of lymphocytes and plasma LDL binding activity to liver non-parenchymal cells of rat in 5 normal persons and endogenous hypertriglyceridemlcs(whose plasma triglycerides levels were 0. 87±0. 32 and 3.07 ±1.67 mmol/L respectively) was made. Plasma LDL was isolated by density gradient ultracentrifugation. LDL receptors of lymphocytes were measured by a enzyme-linked method developed by this laboratory.125 I-labelled-LDL was prepared by IC1 method. Liver non-parenchymal cells(NPC) of rat were prepared by collagenase method.125ILDL binding to rat liver NPC was measured by Goldstein and Brown' s method. The results showed that the Bmax of LDL binding to lymphocytes from hypertriglyceridemic group was significantly higher than that of normal group(57.5±13.2:38.2±9.3 ng/mg cell protein,p<0. 05), but there was no difference in affinity(Kd) between the normal and hypertriglyceridemic groups(12.0±3.2:13.3±4.1μg/ml, p>0. 05).The binding activity of plasma LDL from hypertriglyceridemics to rat liver NPC was significantly lower than that of LDL from the normal group(p<0. 05). The results are disscused.