A　new　method　for　algal　community　restructuring　is　proposed,　where　harmful　algae　growth　is　inhibited　through　the　addition　of　remedial　nano-agent,　while　probiotic　algae　growth　is　promoted　or　only　affected　indistinctively.　In　this　paper,　the　inhibiting　effects　of　five　different　nanomaterials　on　Microcystis　aeruginosa　(M.　aeruginosa)　and　Cyclotella　sp.　were　studied,　and　the　optimal　nanomaterial　was　served　as　algae-inhibition　ingredient　of　the　remedial　agent.　The　effects　of　the　remedial　agent　on　algal　growth　and　their　physiological　characteristics　were　investigated,　and　the　restructuring　of　algal　community　in　actual　water　samples　was　explored.　The　results　indicated　that　the　inhibition　ratio　of　10　mg/L　nm-Cu2O/SiO2　on　M.　aeruginosa　and　Cyclotella　sp.　could　reach　293.1%　and　82.8%　respectively,　acting　as　the　best　candidate　for　algae-inhibiting　ingredient.　After　adding　the　remedial　nano-agent　made　with　nm-Cu2O/SiO2,　the　content　of　chlorophyll　a,　protein,　and　polysaccharides　of　M.　aeruginosa　decreased　sharply,　while　the　physiological　characteristics　of　Cyclotella　sp.　were　not　significantly　affected.　Besides,　the　total　biomass　and　proportion　of　cyanobacteria　dropped　(P　＜　0.05),　but　the　Bacillariophyta　biomass　increased　significantly　(P　＜　0.05).　The　uniformity　index,　Shannon-Wiener　index,　and　richness　index　all　increased　significantly　(P　＜　0.05).　Meanwhile,　the　quality　of　actual　water　samples　has　been　improved　evidently　(P　＜　0.001).　Therefore,　the　prepared　remedial　nano-agent　in　this　study　can　control　the　harmful　algae　bloom　to　a　certain　extent　by　restructuring　the　algal　community　in　eutmphic　water　bodies.