Si0.82Ge0.18/SOI prepared by epitaxial growth of SiGe layer on SOI wafer in the ultra-high vacuum chemical vapor deposition is used to fabricate the SiGe on insulator (SGOI) substrate (0.24≤xGe≤1) by the cyclic oxidation and annealing processes. The structure and the optical properties of the SGOI with various Ge content are studied by employing HRTEM, Raman spectroscopy, and photoluminescence (PL) spectroscopy. The variations of Ge component and strain in the oxidation process are analyzed. High crystal quality Ge on insulator (GeOI), with a thickness of 11 nm, is obtained with a flat Ge/SiO2 interface. The direct band transition photoluminescence of the GeOI is observed at room temperature. The photoluminescence peak from GeOI is located at 1540 nm, and the PL intensity increases linearly with exciting power increasing. It is indicated that the formed GOI material has a high crystallization quality and is suitable for the applications in Ge optoelectronic and microelectronic devices.