Abstract: Objective:To study the preoperative application value of magnetic resonance arteriography(MRA) and magnetic resonance venography(MRV) in intracranial tumor.Methods:Twenty patients with intracranial tumor dignosed by pathology were detected by MRI,MRA and/or MRV before operation.The preoperative image data were compared with the intraoperative findings.Results:Among 18 cases examined by MRA,4 cases with blood supply artery abnormal enlargement and 6 cases with intracranial major vascular oppressed,moved and embedded by tumor were found.Among 12 cases examined by MRV,6 cases with venous sinus invaded and 4 cases with venous sinus oppressed and moved by tumor were found.Three cases with draining vein enlargement were found.The intraoperative findings were highly consistent with the preoperative MRA and MRV images.Conclusions:MRA and MRV can clearly display the anatomical relationships between intracranial tumor and major blood vessel,which can provide the precise image information for formulating reasonable operation scheme.