Abstract：Objective：To observe the clinical efficacy and safety of Ruanmai Xiaoban Decoction in the treatment of vulnerable carotid atherosclerotic plaques of phlegm blended with blood stasis type．Methods：A total of 104 patients with vulnerable carotid atherosclerotic plaques admitted to Wenzhou Hospital of Traditional Chinese Medicine from January to December 2024 were selected and randomly divided into the western medicine group and the combination group using the random number table method， with 52 cases in each group． The western medicine group received Atorvastatin treatment，while the combination group received Ruanmai Xiaoban Decoction in addition to the treatment regimen of the western medicine group． Both groups were treated for 12 weeks． Changes in plaques， blood lipids， hemorheology， as well as clinical efficacy and safety were compared between the two groups． Results： After treatment， the intima-media thickness （IMT）， total plaque thickness， total plaque area， traditional Chinese medicine syndrome score，low-density lipoprotein cholesterol （LDL-C），triglycerides （TG），total cholesterol （TC）， plasma viscosity，whole blood low-shear viscosity，and whole blood high-shear viscosity decreased in both groups（ P＜ 0.05）． Moreover， all the above indicators in the combination group were lower than those in the western medicine group （P＜0.05）． The total effective rate of clinical efficacy was 67.31% （35/52） in the combination group and 46.15% （24/52） in the western medicine group，with significant difference between the two groups （P＜0.05）．There was no statistically significant difference in the incidence of adverse reactions between the two groups （P＞0.05）． Conclusion：Ruanmai Xiaoban Decoction is effective in the treatment of vulnerable carotid atherosclerotic plaques of phlegm blended with blood stasis type． It can stabilize plaques， improve traditional Chinese medicine symptoms， regulate blood lipids and hemorheology，and shows good safety.