Measurements of magnetization and ac-susceptibility of Fe-Zr amorphous alloys over the wide composition range have been carried out. The spin glass like behavior appears in two different regions of composition. The spin glass behavior in Fe-rich Fe amorphous alloys (around 90 at.% Zr) is due to the frustration of antiferromagnetic coupling between spins. The other behavior around 50 at.% is due to the dilution of atoms with magnetic moment. They are explained by the local environment effect
