To observe the clinical efficacy and safety of self-made Shengji decoction in prevention of infection after cesarean section.Methods：Two hundred pregnant women admitted to our hospital from March 2009 to March 2013 and received caesarean section for the delivery were randomly divided into observation group (n=100) and control group (n=100).Patients in control group received intravenous drip of 1g Cefazolin diluted in 100ml sodium chloride， 1g per time， 2 times per day for 3 to 5 days; Observation group gave patients intravenous drip of 1g Cefazolin diluted in 100 ml 0.9% sodium chloride， 1 g per time， 1 time a day for 3 days， as well as oral administration of self-made Shengji decoction.Patients’ body temperature after recovery， uterine cavity， abdominal incision infections， pelvic infections， urinary tract infections and drug-economic-efficiency indexes (inpatient days， inpatient costs)， and adverse reactions were observed and compared.Results：Neither group occurred uterine cavity， pelvic cavity， or urinary tract infections; the patients’ postoperative body temperature， wound healing， and hemogram showed no significant differences (P>0.05); there was significant difference between the two groups in terms of inpatient days and hospital costs (P<0.05); there was no adverse reactions in either group.Conclusion：Self-made shengji decoction can effectively prevent infection in postoperative cesarean section and shorten patients ' hospital stay and reduce hospital costs， and it is worth clinical application.