ZnO nanorods are modified by Sn ion and investigated their physical characteristics. The effects of seed layers prepared by sputtering and spin-coating methods on the FTO glasses were also studied. ZnO nanorods were synthesized by a sonochemical method using a zinc acetate dehydrate as a precursor. The Sn-doped ZnO nanorods were synthesized using a tin tetrachloride by a sonochemical method. The characteristics of well-aligned ZnO nanorods were investigated by a FE-SEM, XRD, photoluminescence (PL) with respect to two aspects such as growth methods of a seed layer and tin tetrachloride ion modifications. The Sn doping can form new band structure in the ZnO nanorods, which can effectively control their light absorption spectra and improve the energy conversion efficiency of the ZnO nanorod-based dye sensitized solar cells (DSSCs).