TiO2 nanorod composites were prepared on the flyash hollow microsphere substrates by a C2H5OH/H2O mixed solvothermal method. The morphology of TiO2 nanorod with different preparation conditions and the growth process was studied. The results reveal that the crystal form of TiO2 nanorods is rutile phase. The morphology and the size of TiO2 nanorod depend on the volume ratio of C2H5OH/H2O, titanium precursor concentration and reaction time. The crystallinity of TiO2 nanorod increases with appropriate ethanol, and also the tetragonal rodlike crystal morphology becomes distinct. The size of TiO2 nanorods gradually increases with the increase of concentration and reaction time. In addition, TiO2 nanorod composites show a better photocatalytic activity in degrading rhodamine B.