As there are high algae content in the eutrophic source water,the bio-filtration process,ozone pre-oxidation/bio-filtration process,potassium permanganate pre-oxidation/coagulation process and coagulation-flotation process are adopted to compare the algae removal.The results show that the algae removal rate by bio-filtration pretreatment process is ranging from 58.55% to 75.89%,and the average removal rate is 69.04%.With an ozone dosage of 1.5mg/L,the algae removal rate by pre-ozonation/bio-filtration process is over 85%.With a PAC dosage of 15mg/L and a potassium permanganate dosage of 0.8mg/L,the algae removal rate by potassium permanganate pre-oxidation/ coagulation-sedimentation process is more than 90%.The algae removal rate by coagulation/flotation process is between 87.86% and 94.18%,with an average removal rate of 90.68%.