We exploit a facile synthetic route to fabricate dendritic SnO2/TiO2 nanodentrites with a twofold point symmetry by a combination of vapor transport deposition method for the SnO2 nanowire backbones and subsequent hydrothermal heteroepitaxial growth of TiO2 nanorod branches. As a result of the good lattice matching and same rutile crystal structures between SnO2 and TiO2, an interface epitaxy is established accounting for the high symmetry. Proof-of-principle demonstration of the function in photoelectrochemical water splitting is presented.