A method of polyacrylic acid-complexation and ultrafiltration for matrix modification and inductively coupled plasma mass spectrometry（ICP-MS）was developed for the determination of 24 trace level of rare earth elements（REEs） and metal elements in coastal and estuarine seawater.REEs ions，Cu2+,Pb2+,Cd2+,Co2+,Ni2+ could reacted with polyacrylic acid（PAA） to form stable complexes when the pH value was above 7.5，which could be separated and enriched absolutely after trapped and eluted from the ultrafilter.Full quantitative data collection mode and internal standard calibration curve were used for the ICP-MS determination.Under the optimized conditions，the relative standard deviations（RSDs） were in the range of 1.7%-7.3%，and the spiked recoveries were between 73% and 96%.The limits of quantitation（LOQs，10σ） ranged from 0.23 ng/L to 13.9 ng/L.The method blank ranged from 0.09 ng/L to 8.38 ng/L.The developed method could be applied in the simultaneous determination of REEs and metal elements in coastal and estuarine seawater.