This study aimed to investigate the effectiveness of anti-atherosclerosis of rosmarinic acid (RosA).This study used a parallel flow chamber to establish low shear stress (LSS)-induced endothelial (EC) dysfunction model.This study exposed EC to LSS (3 dyn/cm2) for 30 min and treated it by oridonin.the ROS and NO levels in EC were measured by DHE and DAF-FM DA assay.The mRNA and protein expression of ICAM-1 and VCAM-1 were assayed by qPCR and Westen blotting.This study fed zebrafish with high-cholesterol diet (HCD) to establish a zebrafish atherosclerosis (AS) model,and observed lipid accumulation and inflammation by a fluorescence microscope.Results found that RosA improved LSS-induced EC dysfunction,and inhibited HCD-induced lipid accumulation,oxidative stress and inflammation.Results indicated that RosA may be used for the treatment of AS,and primarily exhibited its protective role through improving LSS-induced EC dysfunction.