Abstract: OBJECTIVE To explore the influence of preoperative antibiotics prophylaxis on postoperative infections and serological infection makers of patients undergoing cesarean section so as to provide objective basis for treatment and prevention of the infections. METHODS A total of 962 puerpera who received cesarean section from Jan 2015 to Dec 2016 were recruited as the study objects and randomly divided into the study group and the control group, with 481 cases in each group.The control group was treated with antibiotics for prevention of infections after the puerpera returned to wards, while the study group was treated with antibiotics for prevention of infections before the surgery for 30 min.The incidence of postoperative infections, infection sites, the highest body temperature, status of incision healing, length of hospital stay and hospitalization cost were observed and compared between the two groups of puerpera.The levels of serum procalcitonin (PCT), C-reactive protein (CRP), tumor necrosis factor(TNF-α) and interleukin-6 (IL-6) were determined and compared between the two groups of puerpera before the surgery and after the surgery for 1 day. RESULTS The incidence rate of postoperative infections was 5.82% in the study group, 9.56% in the control group; the incidence rate of puerperal infections was 0.21% in the study group, 2.08% in the control group, and there were significant differences between the two groups (P＜0.05).There was no significant difference in the highest body temperature or incision healing grade between the two groups of puerpera.The length of hospital stay was (4.26±0.41) days in the observation group, shorter than that in the control group; the hospitalization cost was (7116.45±282.36)yuan in the observation group, less than that in the control group (P＜0.05).There were no significant differences in the levels of serological infection markers between the two groups of puerpera before the surgery.The levels of serum PCT, CRP, IL-6 and TNF-α were respectively (3.12±0.52)μg/ml, (8.15±1.51)mg/ml, (78.82±6.39)pg/ml and (53.18±5.64)pg/ml in the observation group after the surgery for 1 day, lower than those in the control group (P＜0.05). CONCLUSION The preoperative intravenous use of antibiotics may reduce the incidence of postoperative infections and levels of serological infection markers of the puerpera undergoing the cesarean section, facilitate the rehabilitation and cut the medical cost.