Abstract: Cave stalagmites,corals,lake sediments are suitable for dating using the thermal ionization mass spectrometry (TIMS)uranium series method.In mass spectrometric determination,more factors should be considered.In this paper,based on the experiments,some factors are analyzed in order to gain a perfectly correct age date.This might do good to the reorganizations of the rules of the past environmental globe changes and serve for the reconstruction of paeloclimates and the forecasts of the future change of climates.