Photocatalysis　is　an　efficient　advanced　oxidation　process　that　provides　a　promising　alternative　for　pollution　control　during　algal　blooms　in　lakes　or　water　reservoirs.　Previous　research　has　mainly　focused　on　the　destruction　of　algal　cells　by　photocatalysis,　whereas　the　release　and　control　of　concomitant　secretions　specially　intracellular　organic　matter　(IOM)　is　undervalued.　Herein,　we　studied　the　removal　efficiency　and　mechanism　of　algal　IOM　extracted　from　Microcystis　aeruginosa　during　stationary　phase　by　the　combined　process　of　pre-photocatalysis　with　a　novel　composite　of　Bi2O3-TiO2/PAC　(Bi-doped　TiO2　nano-composites　supported　by　powdered　activated　carbon)　followed　by　enhanced　coagulation　with　aluminum　sulfate　(AS)　coagulant.　Optimized　photocatalysis　and　coagulation　combined　treatment　(PC)　was　indicated　to　enhance　IOM　removal　with　64%,　92%　and　100%　for　DOC,　absorbance　at　254　nm　(UV254)　and　the　optical　density　at　680　nm　(OD680)　respectively.　Pre-photocatalysis　reduced　the　required　AS　coagulant　dose　and　weakened　the　effect　of　solution　pH.　Photocatalysis　was　more　inclined　to　remove　humic　substances　and　building　blocks　than　high-molecular　weight　components,　while　coagulation　alone　displayed　preference　for　high-molecular　weight　biopolymers　and　protein-like　substance.　Pre-photocatalysis　was　complementary　with　subsequent　coagulation　for　efficient　removal　of　protein-like　sub-stances　and　fractionation　with　medium　molecular　weight　of　0.5-1　kDa.　The　produced　flocs　revealed　that　the　Bi2O3-TiO2/PAC　adsorbing　IOM　acted　as　a　flocculation　core　to　improve　coagulation　performance.　Besides,　the　combined　PC　process　was　proved　to　perform　well　to　co-existing　algal　pollution　without　damaging　cells　integrity　and　enhanced　algal　cells　removal　from　26%　by　coagulation　alone　to　61%.　Therefore,　this　combined　treatment　was　an　effective　method　for　the　removal　of　IOM　of　Microcystis　aeruginosa　and　control　cyanobacteria　bloom.