Rare Earth Elements (REEs) play an important role on understanding and studying hypergene processes.As of the chemical characteristics,input resources,migration and fractionation of REE in hypergene water,the complete process of REE′s activation and re fractionation is summarized,and the significance of REE in natural water and paleo sediments is also discussed by shale relative to deeper sea sediments.Considering the mistake found in the analytical means,it is necessary to recorrect the past wrong conclusions and to re estimate the geological significance of REE in water and evolution of lithosphere as well as other sediments.