Abstract: OBJECTIVE To analyze the related factors of cerebrospinal fluid infection in patients with brain tumor after operation. METHODS The clinical data of 225 patients with brain tumor undergoing neurosurgery at the Second Affiliated Hospital of Hainan Medical College from May 2016 to Mar. 2017 were retrospectively analyzed. The related factors of cerebrospinal fluid infection of brain tumor after operation were analyzed. RESULTS A total of 79 patients in 225 patients had cerebrospinal fluid infection, and the incidence was 35.11%. There were 2 deaths in 79 patients with CSF infection, and the rest of the patients returned to normal after treatment. The age, tumor volume, external ventricular drainage, extracranial infection, malnutrition, anemia, hypoproteinemia and diabetes were related factors affecting cerebrospinal fluid infection after cerebral tumor surgery (P<0.05). CONCLUSION There are a variety of factors affecting postoperative cerebrospinal fluid infection in patients with brain tumors. In clinical work, targeted interventions should be taken to prevent such factors and reduce the risk of cerebrospinal fluid infection after brain tumor surgery.