EN
Structural changes of Co_{66}Ni_{12} Si_9B_{13} amorphous alloy, stimulated by isochronal and isothermal annealing, were observed by means of the methods: electrical resistivity, Hall effect and X-ray diffraction. In the amorphous matrix at the temperature 673 K phasesα-Co and (Co,Ni)_5Si_2B are created, while at the temperature 773 K the phase (Co,Ni)_3B is formed. The structural phase transitions are related to abrupt decrease in electrical and Hall resistivities at the background of systematic decrease in these parameters values during the alloy transition from the amorphous to the crystalline state.