In this study, one strain of algicidal bacterium H01 was selected from the water body polluted by Microcystis aeruginosa. It had good removal effects on Microcystis aeruginosa and the removal characteristics on Microcystis aeruginosa were studied. The results indicated that the removal efficiency was connected with such factors as temperature and pH. And the experiment on algicidal mechanism indicated that it lysed the algae cells by secreting metabolites. According to the analysis of its physiological characteristics and 16S rDNA gene sequence, the strain H01 was identified as Brevibacillus parabrevis.