Abstract: Atherosclerosis (AS) is a chronic inflammatory disease, the main causes of which include abnormal lipid metabolism, endothelial injury, physical and chemical injury, hemodynamic injury, genetic factors and so on. These causes can lead to inflammatory injury of blood vessels and local dysfunction. Bunao-Fuyuan decoction (BNFY) is a traditional Chinese medicine compound that can treat cardiovascular and cerebrovascular diseases, but its effect on AS is still unknown. The aim of this study was to investigate the effect and mechanism of BNFY in proliferation and migration of vascular smooth muscle cells (VSMCs) on AS. At first, the expression of α-SMA protein in ox-LDL-induced VSMCs, which was detected by immunofluorescence staining and western blot. CCK-8 technique and cloning technique were used to detect the cell proliferation of ox-LDL-induced VSMCs after adding BNFY. Meanwhile, the expression of proliferating protein Ki67 was detected by immunofluorescence staining. Western blot was also used to detect the expression of proliferation-related proteins CDK2, CyclinE1 and P27. Flow cytometry was used to detect the effect of BNFY on cell cycle. The effects of BNFY on proliferation and migration of cells were detected by cell scratch test and Transwell. Western blot was used to detect the expression of adhesion factors ICAM1, VCAM1, muc1, VE-cadherin and RHOA/ROCK-related proteins in cells. We found that the expression of AS marker α-SMA protein increased significantly and cells shriveled and a few floated on the medium after induction of ox-LDL on VSCMs. The proliferation rate of ox-LDL VSMCs decreased significantly after adding different doses of BNFY, and BNFY can inhibit cell cycle. Meanwhile, we also found that cell invasion and migration rate were significantly inhibited and related cell adhesion factors ICAM1, VCAM1, muc1 and VE-cadherin were inhibited too by BNFY. Finally, we found that BNFY inhibited the expression of RHOA, ROCK1, ROCK2, p-MLC proteins in the RHOA/ROCK signaling pathway. Therefore, we can summarize that BNFY may inhibit the proliferation and migration of atherosclerotic vascular smooth muscle cells by inhibiting the activity of RHOA/ROCK signaling pathway.