Crystal　orientation-ordered　hexagonal　Zn2GeO4　nanorod-bundles　have　been　obtained　via　a　synergistic　self-assembly　route.　Each　nanorod　unit　of　the　bundles　maintains　its　individual　hexagonal　rod-shaped　structure　and　is　dominated　by　(110)　and　(110)　facets,　and　all　of　them　are　aligned　parallel　to　the　growth　direction　in　a　high　density.　An　ordered　self-assembly　of　anisotropic　nanorods　was　suggested　to　elucidate　the　formation　of　the　unique　bundle　structures.　The　novel　structure　of　Zn2GeO　4　bundles　assembled　from　hexagonal　nanorods　leads　to　a　surprisingly　high　UV-light-driven　activity　for　the　photocatalytic　decomposition　of　water-methanol　solution　to　hydrogen.　The　correlation　of　structure　and　photocatalytic　activity　of　the　ordered　nanorod-bundles　was　discussed,　indicating　a　new　strategy　of　bundling　Zn2GeO4　nanorods　with　reactive　facets　to　effectively　enhance　photocatalytic　activities　of　1-D　nanostructures.　©　2013　The　Royal　Society　of　Chemistry.