An electrodeposition route for preparation of well-controlled magnesium hydroxide nanostructure using sodium acetate as structure-directing agent was presented. The magnesium hydroxide thin films were characterized by XRD, SEM and TEM. The influence of synthesis parameters on the morphological characteristics and size of magnesium hydroxide thin films deposited from nitrate bath was investigated, such as concentration of sodium acetate additive and applied potential. A possible mechanism responsible for morphologies evolution of thin films was also elucidated. This electrochemical process may be extended to fabricate other nano-/mesostructures with diverse morphologies and unique properties under convenient and mild conditions. (c) 2007 Published by Elsevier B.V.