In this paper, in order to explore the effect of plants on the removal of total phosphorus in eutrophic water, the emergent plant iris was selected as the research object, and the simulation experiment was carried out. The results showed that after a sampling interval of 7 days, the total phosphorus content in the water body decreased by 8.2% to 19%; after a sampling interval of 14 days, the total phosphorus content in the water body decreased by 26.8% to 43.7%; after a sampling interval of 21 days, the total phosphorus content in the water body decreased by 35.0%~53.5%; after a sampling interval of 28 days, the total phosphorus content in the water body decreased by 40.2%~61.3%; after a sampling interval of 35 days, the total phosphorus content in the water body decreased by 39.2%~64.0%; after a sampling interval of 42 days, the total phosphorus content in the water body decreased by 41.2%~65.7%. Experiments show that iris has a certain effect on removing phosphorus polluted water bodies.