Aim To study the mechanism of microRNA-155(miR-155) depending on cholesteryl ester hydrolase(CEH) to influence foam cells formation. Methods Oil red O staining and HPLC were used to analyze cholesteryl ester content, and the positive cells and cholesterol ester content were observed. Western-blot was used to the expression of CEH, ATP binding cassette transporter A1(ABCA1), scavenger receptor AⅠ(SR-A). Results The positive cell ratio and the cholesterol efflux were dramatically decreased by miR-155 mimics(P＜0.05);the positive cell ratio, the cholesterol efflux, the expression of SR-A were significantly decreased(P＜0.05),while the expression of CEH and ABCA1 were significantly increased in miR-155 mimics group respectively(P＜0.05). The expression of SR-A,the positive cell ratio, the cholesterol efflux were significantly increased(P＜0.05), while the expression of CEH and ABCA1 were significantly decreased in microRNA-155+siRNA-CEH group and siRNA-CEH group respectively(P＜0.05). Conclusion The high expression of microRNA-155 can inhibit the formation of foam macrophages,which may be enhanced by CEH affecting the expression of ABCA1 and SR-A.