A novel cubane-type ZnO (CBE-ZnO) polymorph is studied by means of the first-principles density functional theory calculations. The results suggest that the CBE-ZnO polymorph is mechanically and dynamically stable. The new CBE-ZnO structure is also energetically more favorable than the previously predicted CsCl-ZnO, BCT-ZnO, and the synthesized RS-ZnO polymorphs. The discovery of CBE-ZnO brings about a complete picture of the extent and nature of polymorphism in ZnO family. (C) 2012 Elsevier B.V. All rights reserved.