The As-Se system has been studied by EMF method in glassy state. On the basis of EMF measurements, the relative partial molar functions of As in glasses calculated. By integration of the Gibbs-Dugem equation, the standard thermodynamic functions of mixture of glasses calculated. It has been established that glass-like solutions AsxSe1-x are characterized by considerable negative deviation from ideality. The comparative analysis of the obtained results with the literary data on the structure of the near order in As-Se glasses carried out.