Chemically synthesized one dimensional germanium nanowires on insulator offer a viable nanomaterial platform for high-performance and low-power electronics. The use of noncontaminating metal catalysts and growth of nanowires on an insulator layer facilitate the direct integration of nanowire components into future nanoelectronic chips. Indium and antimony were used as catalysts for germanium nanowire growth in a simple thermal evaporation process. The self-assembly of germanium nanowire on insulator follows the vapor-liquid-solid process. Results show that the nanowires, 10–20nm in diameter and tens of microns in length are single crystals with a diamond cubic lattice structure and grow preferentially along the ⟨111⟩ crystallographic direction.