Customized hierarchical porous metal oxide arrays is of great importance for construction of high-performance electrochemical devices. In this work, we report hierarchical porous (HP)-NiO sheets arrays by a facile hydrothermal method. Interestingly, the obtained NiO sheets arrays show HP systems, and are composed of cat-ear-like sheets main structure and interconnected nanosheets secondary structure. Moreover, the secondary nanosheets are highly porous and consist of cross-linked nanoparticles of 30-100 nm. The electrochemical performances of the HP-NiO sheets arrays are evaluated as anode for Li ion batteries. Compared with the normal NiO sheets arrays, enhanced electrochemical performances are achieved for the HP-NiO sheets, including higher capacity, better cycling life and high-rate capability. The HP-NiO sheets can deliver a specific capacity of 511 mAh g(-1) at 3 A g(-1), higher than the normal NiO sheets arrays (374 mAh g(-1) at 3 A g(-1)), due to the hierarchical porous array configuration with large surface area, fast ion diffusion path and better accommodation of volume change. (C) 2015 Elsevier Ltd. All rights reserved.