Abstract: AIM:To investigate the effect of high glucose on expression and function of ABC transporters in THP-1 monocyte-derived macrophages (MDM). METHODS: THP-1 MDM were incubated with different doses of D-glucose for 5 days. Real-time PCR and Western blotting were used to measure the expression of ABCG1 and ABCA1 and enzymatic fluorometric method was used to measure cholesterol content in cells and media after glucose-incubated macrophages were treated by LDL and HDL. RESULTS: High glucose reduced the levels of ABCG1 mRNA and protein in MDM in a dose-dependent manner. However, expression of ABCA1 was not influenced by high glucose. With the increasing glucose, cholesterol efflux regulated by HDL decreased and intracellular cholesterol accumulation increased. CONCLUSION: High glucose decreases the expression of ABCG1 and cholesterol efflux in MDM and contributes to intracellular cholesterol accumulation.