Glasses of binary systems (Sb2S3-As2S3 and Sb2Te3-As2S3) and ternary sections (containing 10, 20 and 40 mol% of Sb2Te3) belonging to Sb2S3-As2S3-Sb2Te3 system were prepared by rapid quenching method in ice water of their liquid phases. From chemical formulas obtained by using Energy Dispersion Spectroscopy (EDS), average values of Sb2S3-As2S3-Sb2Te3 glasses’ parameters such as coordination number (Z), atomic radius (Rav), atomic number (Zav), atomic molar mass (Mav) and electronegativity (av) were calculated. These parameters were used to explain the formation of the glasses in the Sb2S3-As2S3-Sb2Te3 system by following their evolution as a function of the As2S3 content.