The purpose of this study was to determine the usefulness of three-dimensional (3D) MR imaging of brain tumors for surgical planning. Sixty-nine patients with various tumors of the brain were included in the present study. Using a volume-rendering (VR) method on an independent workstation, 3D-MR images were obtained with the fast-SPGR sequence after Gd-DTPA administration. VR images could show an exact relationship between the surface of the brain and major vessels. However, in patients with deeply located tumors, VR images did not necessarily provide sufficient information as to the relationship between the tumor and vessels. In combination with a surface-rendering method, 3D-MR imaging could demonstrate the exact relationships among the tumors, major vessels, and surface of the brain. In tumors without contrast enhancement, this method was able to show 3D images of tumors with surrounding structures. For neurosurgeons, 3D-MR images were useful for understanding the surface anatomy and surrounding structures of the tumors prior to surgery. These images were also helpful in explaining the condition of the disease to patients and their families.