We report the synthesis of Cu2S nanocrystalline thin film directly on indium tin oxide (ITO) substrate by a facile hydrothermal method using glutathione as the capping agent. The morphology and the phase composition of the obtained Cu2S nanostructure film are characterized by X-ray diffraction and field emission scanning electron microscopy. A capping agent directed two-step growth mechanism is proposed based on investigation of the reaction condition dependent product morphology. Optical study shows that Cu2S crystalline film has a broad spectrum response over visible and near-infrared region. The current-voltage results from ITO/Cu2S/Al devices indicate that Cu2S film with larger crystal size has better conduction capacity. (C) 2012 Elsevier B.V. All rights reserved.