Abstract: Laboratory simulation experiments were carried out to explore the effect of removing phosphorus and controlling phytoplankton from eutrophic water by using Phoslock^®-diatomite.The result showed that the removal rate of 1.2Phl+80 mg/L DM was the highest for TP,reaching 65.9%,following by 1.5Phl+80 mg/L DM,reaching 55.0%.The removal rate of SRP was mainly related to the dosage of Phoslock^®,however,the SRP removal rate did not change significantly when the dosage was higher than 1.2 Phl.Meanwhile,the abundance of phytoplankton decreased significantly in all experimental groups,and the phytoplankton species structure changed;1.2Phl+80 mg/L DM and 1.5Phl+40 mg/L DM had good inhibition rates,as 74.1% and 81.8% respectively.And there was no significant difference between the two groups in controlling algage.In summary,using the dosage of 1.2Phl +80 mg/L DM Phoslock^®-diatomite could achieve better phosphorus removing and algal controlling,In addition,it had a lower cost.So using Phoslock^®-diatomite was expected to be applied in the actual management of eutrophic water.