The invention discloses a cleaning process for a wide-width ultra-thin copper belt. The cleaning process comprises the following steps of unwinding, degreasing cleaning, pickling washing, grinding, passivation drying and rewinding. According to the cleaning process for the wide-width ultra-thin copper belt, the simple process method is adopted, emulsions, oil stains, oxides and other pollutants onthe surface can be effectively and thoroughly removed, the cleaning time is shortened, the cleaning efficiency is improved, and meanwhile the loss of the belt is reduced.