Objective:To evaluate the clinical efficacy and safety of Ruanmai Decoction that has the effects of tonifying kidney and invigorating qi in the treatment of carotid atherosclerosis with syndrome of kidney essence deficiency. MethodsA total of 98 patients of carotid atherosclerosis with syndrome of kidney essence deficiency were randomly divided into the treatment group and control group,49 cases in each group. The control group was treated with the conventional therapy of western medicine,and the treatment group was treated with Ruanmai Decoction based on the treatment for the control group,with a course of 6 months. The efficacy and safety indexes such as carotid intima-media thickness (IMT),plaque area and endpoints incidence were compared in both groups before and after treatment.  Results:After treatment,the IMT of the treatment group was decreased(P<0.01),while the IMT of the control group was increased(P<0.01). The IMT difference of treatment before and after in the treatment group was greater than that in the control group(P<0.01). After treatment,the plaque area of the treatment group was decreased(P<0.05),and the plaque area difference of treatment before and after in the treatment group was greater than that in the control group(P<0.01). The incidence rates of cumulative endpoints and secondary endpoints in the treatment group were lower than those in the control group (P<0.05).  Conclusion:Ruanmai Decoction combined with conventional therapy of western medicine can inhibit the thickening of carotid atherosclerosis,delay the progress of plaque area and reduce the incidence rate of clinical endpoints.