Abstract: OBJECTIVE To investigate the risk factors of postoperative infections and changes of inflammatory factors and T lymphocyte subsets in cesarean section, so as to provide guidance for clinical practice. METHODS A total of 421 cases of cesarean section from Dec. 2015 to Dec. 2016 were chosen as the research subjects. The incidence of postoperative infections was statistically analyzed. The risk factors of infection were analyzed. The serum inflammatory factors and T lymphocyte subsets for the infected patients and non-infected patients were observed and compared. RESULTS Totally 20 cases were with postoperative infections in the 421 cases of cesarean section maternal, and the infection rate was 4.75%. The infection sites were mainly concentrated in the surgical incision and reproductive system. Age, ventilator application, catheter application, length of stay, duration of operation, and diabetes mellitus were independent risk factors for postoperative infections (P<0.01). The levels of TNF-α, IL-4, IL-6, IL-8 and IL-12 in patients with infection were (24.30±7.12)ng/L, (96.28±40.22) ng/L, (253.96±50.22) ng/L, (99.93±38.21) ng/L and (134.13±43.21) ng/L, which were significantly higher than those in non-infected patients (P<0.05). The CD₃⁺ CD₄⁺ and CD₃⁺ CD₈⁺ in patients with infection were (410.21±105.54) and (321.21±131.34)/μl, which were lower than those in non-infected patients (P<0.05). CONCLUSION The postoperative infection of cesarean section should be caused clinical attention, should be paid attention to observe the changes of the patient's clinical indicators, and should be taken targeted intervention according to the targeted risk factors of infection, thereby effectively reducing the infection rate.