The EXAFS of amorphous semiconductor a-As2Se3, a-AsSe, a-As0.05 Se0.95 and a-As2Se3) after annealing at different temperatures lower than Tg are measured by 12 kW rotating anode X-ray diffraction equipment. Analyses of the determined radial structural functions shows that although the short range structure of a-As2Se3 is very similar to that for crystalline As2Se3, some changes take place in its radial structural function after annealing. The structural relaxation in a-As2Se3, quenched from melt, has also been observed. The short range structures for different components of As in binary As-Se system seem to be different.