Abstract：Plant invasion is taken as the important driving factor of soil carbon （C）， nitrogen （N） and phosphorus （P） cycle in estuarine wetland. In order to explore the impact of Spartina alterniflora invasion on the Cyperus malaccensis wetland on carbon input and emission in the Minjiang River estuarine wetland of Fujian Province， the contents and storages of soil C， N and P， methane （CH4） and carbon dioxide （CO2） emissions were measured and analyzed. The results showed that： ①Spartina alterniflora invasion Cyperus malaccensis wetland increased the contents of soil C， N at 0~60 cm and soil P at 0~15 cm（p<0.05）； ②The C， N and P storages of soil at 0~60 cm increased by 16%， 46% and 26% after Spartina alterniflora invasion Cyperus malaccensis wetland（p<0.05）； ③Soil C/N at 0~15 cm and 15~30 cm decreased by 33% and 24%， and soil C/P at 15~30 cm decreased by 31% after Spartina alterniflora invaded Cyperus malaccensis wetland（p<0.05）. ④Spartina alterniflora invasion Cyperus malaccensis wetland increased the average and cumulative emissions of CH4 and CO2（p<0.05）. ⑤Soil C， N and P were positively correlated with CO2 and CH4 emissions（p<0.05， p<0.01）， microbial biomass carbon（MBC） was positively correlated with CH4 emissions（p<0.01）， and C/N was negatively correlated with CH4 emissions（p<0.05）. As a result， Spartina alterniflora invasion enhanced soil C， N， P sequestration and CH4 and CO2 emissions， which was regulated by ecological stoichiometry. The findings of this study can expand the understanding of biogeochemical cycles in estuarine wetlands under plant invasion scenarios.