Measurements of electrical resistivity after low temperature fast neutron irradiation are made for amorphous Pd80Si20and Pd80Ni2Sl18and then Pd80Si20annealed at 230°C and 360°C, and the isochronal annealing curves are obtained. The resistivity increase of Pd80Si20annealed at 360°C is about 10 times larger than that of amorphous alloys and no defined annealing stage is observed in amorphous alloys and Pd80Si20annealed at 360°C. For amorphous Pd80Si20, about 60% of the resistivity increase by irradiation remains after annealing up to room temperature and these are discussed by the structural relaxation.