Abstract: The effects of substrate pretreatments,such as modifying the substrate with ZnO nanoparticles,drying the substrate with highly pure nitrogen and soaking the substrate with hydrochloric acid,on the growth of ZnO micro/nanotube arrays were systematically investigated by using a hydrothermal method.The relationship between substrate surface characteristics and the growth of ZnO micro/nanotube arrays was discussed based on ZnO microstructure.It is indicated that ZnO micro/nanotube arrays with different sizes,morphologies and distributions can be obtained on indium-tin oxide(ITO) substrates pretreated by highly pure nitrogen and hydrochloric acid,respectively.The growth mechanism of ZnO micro/nanotubes showed that the Zn-atom surface termination of ZnO played the key role for formation of the micro/nanotubes.