Discovering functional applications of metallic glasses (MGs) as heterogeneous catalysts is a fundamental and essential topic. This work reports the rapid production of sulfate radicals (SO4[rad]−) from peroxymonosulfate (PMS) using Fe73.5Si13.5B9Cu1Nb3 glassy ribbons as catalysts for Eosin Y (EY) dye wastewater treatment. The reaction rates (k) from the experimental data reveal that the EY degradation is well fitted with the pseudo-first-order kinetic model. The strong electron transfer ability is characterized by electrochemical methods, presenting an advanced catalytic performance for EY degradation. Various experimental parameters, including dye concentration, catalyst dosage, PMS concentration, light intensity, pH and reaction temperature as well as the saline and natural inorganic effects, are fully investigated. The results show that the color removal of EY dye could achieve nearly 100% within 20 min. The quenching experiments are performed to verify the production of reactive species, suggesting that both [rad]OH and SO4[rad]− are produced from PMS and play significant roles in EY degradation. This critical study reveals that using Fe73.5Si13.5B9Cu1Nb3 MGs as catalysts exhibits a superior reactivity on PMS activation in wastewater treatment. The discoveries shed lights into the study of electron transfer ability for MGs, presenting extensive prospects in the application of dye wastewater treatment.