Objective To analyze the incidence and risk factors of central nervous system infection(CNSI)after craniotomy.Methods Clinical data from 1 432 patients who underwent craniotomy in the neuro-surgery department of the hospital from 2019 to 2021 were retrospectively collected,and the positive rates of CNSI after craniotomy in neurosurgery were analyzed.Univariate analysis and multivariate logistic regression analysis were adopted to identify the risk factors affecting the occurrence of CNSI.Results The positive rate of CNSI in 1 432 patients was 12.92％,and the positive rate of bacterial culture in cerebrospinal fluid samples was 2.88％.Univariate analysis showed that hypertension,length of hospital stay,preoperative length of hos-pital stay,intensive care unit(ICU)treatment,American Society of Anesthesiologists(ASA)grading,surgery time≥ 3 h,blood transfusion,cerebrospinal fluid leakage,and postoperative hormone use were influencing fac-tors for the occurrence of CNSI.Multivariate logistic regression analysis showed that hypertension(OR=1.475),length of hospital stay higher than 30 days(OR=2.498),length of ICU treatment(OR=2.381),length of surgery(OR=1.572)higher than 3 hours and cerebrospinal fluid leakage(OR=3.062)were inde-pendent risk factors for the occurrence of CNSI.Conclusion The positive rate of CNSI after craniotomy is rel-atively high,and there are many related risk factors.Medical staff should take relevant measures to address the risk factors,continuously carry out targeted monitoring,and provide a basis for clinical treatment.