Abstract: Objective：To explore the method to construct the three-dimensional of the presacral venous plexus based on Magnetic Resonance Angiography（MRA）， observe the vascular anatomy of the presacral space. Methods：The original Dicom datasets were obtained from 10 young healthy nulliparous woman by MRA in Nanfang Hospital of Southern Medical University in October 2012. Then the pelvic venous vascular network，pelvis，pelvic artery vascular were reconstructed by inputting the datasets into Mimics 10.01 software. Results：The digital three-dimensional models of pelvic venous vascular network was built， which could clearly show middle sacral vein，transverse veins，and lateral sacral vein. Combined with the view of venous vascular network with pelvis and pelvic arterial vascular network，the anatomic structure and drainage region of pelvic veins are much more clearer. Conclusions：To construct the three-dimensional of the presacral venous plexus based on MRA is an effective method to investigate the relative safety area anatomy， which has better clinical utility.

Key words: Magnetic resonance angiography, Image processing, computer-assisted, Preasacral venous plexus