The existence of aluminum in rare earth lixivium seriously affects the extraction of rare earth content. Traditional aluminum removal process using ammonium bicarbonate as precipitant often associate with high rare earth loss and ammonia–nitrogen pollution. For the first time, decyl glucoside (DG), a green and effective precipitant, was employed as an alternative for ammonium bicarbonate to remove aluminum in rare earth lixivium derived from ion-absorbed rare earth ore. In impurity removal experiments, it was found that DG has a better selective removal effect on aluminum in yttrium rich rare earth lixivium with the condition of low rare earth loss rate.Mechanism research results suggest that DG can not only remove most aluminum impurities in rare earth lixivium through hydrolysis neutralization, but the hydroxyl group on the pyran ring of DG can adsorb the aluminum by generating Al-O bond to form complex precipitates. This work provides a potential reagent for effective and green removal of aluminum impurity content from lixivium.