The influence of electrolytic hydrogenation on the magnetic properties of three kinds of soft magnetic amorphous alloys with diffrent composition has been investigated. The experimental results showed that, after hydrogenation, the samples became very brittle and the soft magnetic properties of these alloys were seriously damaged, but the saturation magnetization and the average hyperfine field Hhf increased remakably. The experiments also showed that the hydrogen escaped gradually from the samples when they were left in air at room temperature and the magnetic and mechanical properties as well as the Hhf could recover gradually.