Objective: To verify the interaction between apolipoprotein AI and scavenger receptors class B type I (SR-BI) , a key process of reverse cholesterol transport, by yeast two-hybrid method and to provide a new target for selecting active substance for reducing lipid in plasma. Method: Apolipoprotein AI and SR-BI gene cDNA from Wistar rat were cloned, and DNA/apoAI and AD/SR-BI were constructed, then co-transformed into yeast strain AH109. Transformants were selected on medium of SD/-Leu/-Trp/-His/-Ade/X-a-Gal and the putative positive clones were identified by yeast mating. Result: Transformants can grow on medium of SD/-Leu/-Trp/-His/-Ade/X-a-Gal and the colonies are blue, an (3- galactosidase assays show that the activity of ou [3-galactosidase are 8 ~ 12U and 10 ~ 40U respectively. After yeast mating, blue colonies can still be seen on medium of SD/-Leu/-Trp/-His/-Ade/X-a-Gal. Conclusion: It is true that there is interaction between apolipoprotein AI and SR-BI.