To investigate the efficacy of Xueyushi Decoction combined with piperacillin sodium and tazobactam sodium in the treatment of erysipelas of lower extremities,and to detect its influence on serum indexes and treatment safety.Methods:From May 2016 to Oct 2018,82 patients with erysipelas of lower extremities were divided into control group and combination group by random number table.The control group received piperacillin sodium and tazobactam sodium,and the combination group received Xuoshi Decoction on the basis of piperacillin sodium and tazobactam sodium for 2 weeks.The therapeutic effect,symptom and sign integral value,serological indexes ［nitric oxide(NO),interleukin-1 beta(IL-1 beta),interleukin-6(IL-6),tumor necrosis factor-alpha(TNF-alpha)］ and the incidence of adverse drug reactions were compared between the two groups.Results:After treatment,the effective rate of treatment in the combined group was higher than that in the control group;the scores of symptoms and signs such as skin color,swelling degree,skin temperature and conscious pain were lower than those in the control group; the levels of serum NO,IL-1beta,IL-1beta,IL-6 and TNF-alpha were lower than those in the control group(P<0.05).During the treatment period,there was no significant difference in the incidence of adverse reactions such as rash pruritus,nausea and vomitin g、constipation and diarrhea between the two groups(P>0.05).Conclusion:Xuanxueshi Decoction is effective in treating erysipelas of lower limbs and has good medication safety.