The pollution from nuclear leaks and nuclear disasters (e.g. radioactive iodine) would cause serious harm to human beings and ecosystems for many years. Cocoon silk and deep eutectic solvents (DESs) are both green substances. DESs are easily synthesized, cheap, highly biocompatible and highly biodegradable. Here, we combine the removal of organic dyes and the capture of radioactive iodine by using green DES-pretreated cocoon silk. It is the first time organic dyes have been removed from wastewater by DES-disrupted silk for the purpose of favourably removing iodine. Organic dyes-captured DES-pretreated cocoon silk could be used to capture iodine efficiently. It opens a new route to dispose of one waste from nuclear energy with organic dyes from wastewater captured by green solvents-pretreated natural silk.