Objective To investigate the effectiveness and safety of Huatan-Quzhuo decoction in combination with western medicine for the treatment of carotid atherosclerotic plaques. Methods A total of 194 patients with carotid atherosclerosis were selected were randomly divided into two groups, 97 in each group. The control group was treated with simvastatin. The observation group was treated with Huatan-Quzhuo decoction on the basis of the control group. The serum levels of interleukin-1 (IL-1), tumor necrosis factor α (TNF-α), malondialdehyde (MDA), and superoxide dismutase (SOD) were observed before and after treatment in the two groups. The Sod, IMT, number of plaques, number of vulnerable plaques and area of plaques, carotid artery intima-media thickness (IMT), number of plaques, number of vulnerable plaques, and area of plaques were detected. Results After treatment, the levels of TC, TG, and LDL-C in the observation group were significantly lower than those in the control group (t were 4.546, 6.712, 4.872, P<0.01). After treatment, the IMT (0.85 ± 0.11 mm vs. 1.08 ± 0.13 mm, t=13.302), number of plaques (0.74 ± 0.36 vs. 1.02 ± 0.42, t=4.985), number of vulnerable plaques (0.24 ± 0.25 vs. 0.41 ± 0.27, t=4.550), and plaque area (50.06 ± 9.73 mm2vs. 68.52 ± 11.24 mm2, t=12.230) in the observation group were significantly lower than those in the control group (P<0.01). The levels of IL-1, TNF-α and MDA in the observation group were significantly lower than the control group (t were 13.089, 4.769, 10.442, P<0.01). The level of SOD was observation group was significantly higher than the control group (t=11.636, P<0.01). Conclusions The combination of Huatan-Quzhuo decoction and western medicine in the treatment of carotid artery atherosclerosis can regulate the level of blood lipids, improve the degree of atherosclerosis, reduce the degree of inflammation and oxidative stress. Key words: Atherosclerosis; Huatan-Quzhuo decoction; Simvastatin; Syndrome of phlegm and blood stasis blocking collaterals