Aim To study the effect of Amlodipine on CD40 expression in HUVEC-12 endothelial cells induced by oxidized low density lipoprotein(ox-LDL) to explore the new antiatherosclerotic role of Amlodipine. Methods The experiment groups included 6 groups: control group,10.0 μmol/L Amlodipine alone treated group,ox-LDL group,and different concentration(0.1,1.0,10.0 μmol/L) of Amlodipine pretreated for 1 h and treated with 50 mg/L ox-LDL for 24 h group.RT-PCR was used to detect the mRNA expression of CD40 and western-blot was used to detect the protein expression of CD40. Results RT-PCR and western blot showed that with ox-LDL and Amlodipine treatment,both mRNA and protein expression of CD40 were greatly decreased in a concentration-dependent manner. Conclusion Amlodipine can have a significant effect on down-regulating CD40 expression induced by ox-LDL.