The influence of annealing in various atmospheres on properties of the undoped SnOx thin films has been studied. The films with thickness of similar to 400 nm have been deposited on glass substrate by a method of magnetron sputtering in argon-oxygen atmosphere at the pressure inside the chamber 0.9 and 2.7 Pa. The dependences of structural and optical properties of SnOx films from temperature of annealing in air, vacuum and atmosphere hydrogen have been investigated. Correlations between the structural and optical properties of tin oxide films were found. (c) 2005 Elsevier B.V. All rights reserved.