Objective To discuss the authenticity of reconstructing the anterior cruciate l igament (ACL) threedimensional digital model of normal adult knee joint by use of MRI. Methods The double knee joint specimens were selected from 20 fresh normal adult corpses and double knee joint of 20 normal adult volunteers, and were scanned with MRI; continuous image data of level thick 1.0 mm were acquired, and then these data were imported into Mimics 10.01 software for three-dimensional reconstruction; and full three-dimensional digital models were built, including the corpse specimens (corpsemodel group) and normal adult (normal model group). The relevance anatomy index of ACL were measured with easuring tool of Mimics 10.01 software, and double knee joint specimens of 20 fresh normal adult corpses were dissected, and the relevance data were measured (corpse specimens group). Results There was no significant difference in all indexes between corpse model group and corpse specimen group (P gt; 0.05), and between corpse model group and normal model group (P gt; 0.05). Conclusion The image data gathered by MRI could reconstruct the ACL three-dimensional digital model of normal adult knee joint, which has authenticity.