Abstract: Objectives:To investigate the effection of atorvastatin on expression of ABCA1 （mRNA，protein） and LXRαmRNA in THP-1 macrophages. Methods: Cultured THP-1 cells were induced to form macrophages by PMA for 48 hours. The macrophages were incubated with atorvastatin in different concention for 24 0r 48 hours. We determined the changes of ABCA1mRNA, protein and LXRαmRNA by reverse trancriptase polymerase chain reaction (RT-PCR) and immuno- histochemistry. Results: The expression levels of ABCA1 mRNA（ratio of relative expression 1.21 vs 1.48） and protein as well as LXRαmRNA(0.87 vs1.12) were decreased in THP-1macrophages when cultured with atorvastatin(10μmol/L) for 24h compared with control. They would be lessen further with the cultured time. Conclusions: Atorvastatin inhibit the expression of ABCA1 mRNA and protein as well as LXRαmRNA of THP-1macrophages in vitro.