Abstract: OBJECTIVE To investigate the correlation between T lymphocyte subsets combined with inflammatory cytokines and nosocomial infection after surgery for limb fractures. METHODS 620 cases of extremities fractures treated by surgery in the hospital from Aug.2014 - Aug.2017 were taken as the research objects, and divided into the infected group and the non-infected group according to the occurrence of postoperative infection.The serum levels of T lymphocyte subsets and inflammatory factors of the patients when admitted to hospital and 24 h after the surgery were determined by flow cytometry.Logistic regression analysis was used to observe their relevance with postoperative infection of the patients. RESULTS At the time of admission and 24 hours after operation, the percentage of CD₄⁺ cells, the ratio of CD₄⁺/CD₈⁺, the percentage of Th1 cells, and Th1/Th2 in the infected group were significantly lower than those in the non-infected group, and the percentages of CD₈⁺ and Th2 cells were significantly higher than those in the non-infected group (P＜ 0.05).The levels of il-6, il-8 and TNF- were all significantly higher in the infected group than in the non-infected group, and the levels of inflammatory cytokines were all significantly higher at 24 h after surgery than on admission (P＜ 0.05).Multivariate Logistic regression analysis showed that the percentage of CD₄⁺ cells, CD₄⁺/CD₈⁺ ratio, Th1 cell percentage, Th1/Th2 ratio, il-6, il-8, and TNF- were the influencing factors of postoperative nosocomial infection in patients with limb fracture (P＜ 0.05). CONCLUSION The combined detection of T lymphocyte subsets and inflammatory factors at the time of admission can effectively assess the risk of postoperative infection, and help to choose corresponding preventive measures to reduce the infection rate, which is worthy of clinical application.