Abstract To clarify the effect of amorphous/amorphous (A/A) interfaces during ion irradiation, the He ion irradiation responses of ZrCu/ZrCuNiAlSi A/A nanolaminates (A/ANLs) as well as ZrCu and ZrCuNiAlSi single-layered amorphous thin films were examined. The results showed the A/ANLs exhibited superior irradiation resistance compared with the corresponding single-layered thin films, as the former possessed better microstructure stability and higher He ion solubility than the latter during He ion irradiation. Besides, A/ANLs having more interfaces exhibited even better irradiation resistance than those having less. The enhanced irradiation resistance of A/ANLs was attributed to the sink effect of A/A interfaces, which effectively reduced the amount of radiation-induced “defects” and He bubbles.