Cuprous oxides with different dendrite morphologies were formed on F-doped tin oxide (FTO) covered glass substrates by potentiostatic deposition of cupric acetate. The effects of pH value (varied from 5.00 to 5.80) of electrolytes on the crystal morphologies of cuprous oxide were studied. Different crystal morphologies of cuprous oxides were obtained by the change of velocity of vertical growth and lateral growth through varying the pH value of electrolyte. The processes of Cu2O dendrite crystal growth were analyzed through SEM images at different deposition times. Photoelectrochemical properties of the Cu2O thin films prepared in the system are also studied. (C) 2010 Elsevier B.V. All rights reserved.