Abstract: OBJECTIVE To analyze the etiological characteristics and risk factors of nosocomial infection in open fracture patients. METHODS A total of 4982 cases of open fracture patients admitted in our hospital during Jan. 2007 to Jun. 2017 were enrolled. The wound secretions were wiped with sterile cotton swab. The isolation and identification of pathogens as well as the drug sensitivity test were conducted using NEW ATB automatic microbial identification and drug sensitivity analyzer (BioMerieux). The gender, age, cause of injury, combination with diabetes mellitus, operation time, hospitalization time, debridement time and prophylactic use of antibiotics were analyzed retrospectively. Univariate and multivariate logistic regression analysis were performed to analyze the variables influencing nosocomial infection of open fracture patients. RESULTS In the 4982 cases of open fracture patients, 105 cases of nosocomial infection occurred, with an infection rate of 2.11%. Among the 105 patients with nosocomial infection, 124 strains of pathogens were isolated and cultured, including 2 strains of fungi accounting for 1.61%, 54 strains of gram-positive bacteria accounting for 43.55%, and 68 strains of gram-negative bacteria accounting for 54.84%. Multivariate logistic analysis showed that combined with diabetes mellitus, operation time of ≥4 h), hospitalization time of ≥14 d), debridement time of ≥8 h and prophylactic use of antibiotics were the influencing factors of nosocomial infection in open fracture patients (P<0.05). CONCLUSION The main pathogens of nosocomial infection in patients with open fractures are Staphylococcus aureus and Escherichia coli. There are many risk factors of nosocomial infection, which should be paid attention to and preventive measures should be taken to reduce the incidence of nosocomial infection.