Purpose: Lipoprotein-associated phospholipase A2 (Lp-PLA2) is involved in the pathogenesis of atherosclerosis, especially in advanced plaques. In the present study, the abilities of darapladib, a selective Lp-PLA2 inhibitor, and lentivirus-mediated Lp-PLA2 silencing on in ammation and atherosclerosis in apolipoprotein E-de cient mice were compared.Methods: Apolipoprotein E-de cient mice were fed on a high-fat diet and a constrictive collar was placed around the le carotid artery to induce plaque formation. e mice were randomly divided into control, negative control (NC), darapladib and RNA interference (RNAi) groups. Eight weeks a er surgery, lentivirus-mediated RNAi construct or darapladib were used to decrease the expression of Lp-PLA2. Plaques were collected ve weeks later for histological analysis. In ammatory gene expression in the atherosclerotic lesions were then determined at the mRNA and protein level.Results: e expression of pro-in ammatory cytokines was signi cantly reduced in the treatment group, compared to nontreatment group, whereas the plasma concentration of anti-in ammatory cytokines increased markedly. Moreover, our results demonstrated a signi cant reduction in plaque lipid content, as well as a rise in collagen content following Lp-PLA2 inhibition. Interestingly, when comparing the two methods of Lp-PLA2 inhibition, animals treated with Lp-PLA2 RNAi were found to exhibit lower plaque areas and enhanced improvement of plaque stability as compared with animals treated with darapladib. Darapladib had no attenuating e ect on atherosclerotic plaque area. ese therapeutic e ects were independent of plasma lipoprotein levels.Conclusions: Lp-PLA2 inhibition by darapladib or lentivirus-mediated RNAi ameliorated in ammation and atherosclerosis in apolipoprotein E-de cient mice. e e ect was more prominent in the RNAi group.