The glass-forming region of the GeSe2-In2Se3-CsI system was reported firstly. The dependence of glass properties on compositions as formulas of (1-2x)GeSe2-x(In2Se3-CsI) and (0.8-x)GeSe2-0.2In(2)Se(3)-xCsI was investigated. Properties measurements include density, DTA, Raman spectra, visible and near infrared, and infrared (IR) transmission spectra. Raman spectra show that [GeSe4/2] and [InSe4-xIx] tetrahedra are the main structural units in the network of the present glass system. Glasses show larger density (4.29-4.51 g/cm(3)), wider optical transmission window from 0.56 to 16 mu m, and higher thermal stability characterized by the bigger Delta T (Delta T=T-x-T-g > 110 degrees C), which make them the promising candidate materials for IR optics.