Two-dimensional (2D) transition metal dichalcogenide nanosheet is attracting increasing attention in energy storage due to unique nanoconstruction and electronic properties. In this work, molybdenum disulfide (MoS2) nanosheet was prepared by a simple hydrothermal method, and its properties were characterized by X-ray powder diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy and transmission electron microscopy. The electrochemical performances of the product were evaluated by cyclic voltammogram, galvanostatic charge-discharge and electrochemical impedance spectroscopy. The MoS2 nanosheet showed a specific capacitance of 129.2 F g(-1) at a current density of 1 A g(-1). In addition, the MoS2 nanosheet electrode showed good cycle property as an excellent electrode material for electrochemical capacitors and the specific capacitance had only a slight decrease after 500 cycles (retention of 85.1%). The excellent electrochemical performance was attributed to the unique morphology of MoS2 nanosheets, which possessed large specific surface area, unique 2D nanostructures and low equivalent series resistance. (C) 2014 Elsevier Ltd. All rights reserved.