ABSTRACT. We sought to investigate the effect of nerve growth factor (NGF) expression on the formation and prognosis of cerebral aneurysms. Forty-eight cases were selected following a diagnosis of cerebral aneurysm using computed tomography angiography and surgical confirmation. Thirty-four cases of healthy deaths were also chosen. The tissue was tested for NGF expression changes by reverse-transcription PCR, Western blot and histopathology, and NGF expression was compared between the cerebral aneurysm and healthy groups. The expression level of NGF in cerebral aneurysm tissue was significantly increased over that observed in control tissue. The abnormal expression of NGF is related to cerebral aneurysms. The elevated expression of NGF in cerebral aneurysms may be associated with a poor prognosis.