To　improve　the　removal　efficiency　of　small　molecular　organics　in　the　secondary　effluent　from　the　wastewater　treatment　plants,　continuous　dosing　coagulation　(CDC)　was　proposed.　Salicylic　acid　(SA)　was　chosen　as　model　small　molecular　organics　to　evaluate　effects　of　initial　pH　value　on　the　removal　performance　in　the　CDC　process　and　the　complexation　characteristics　of　SA　and　aluminum.　The　CDC　process　with　initial　pH　6had　the　best　removal　efficiency　that　was　13.8%　higher　than　that　of　conventional　coagulation　(CC).　But　the　CDC　process　with　initial　pH　5　and　7　had　limited　promotion　effect.　According　to　the　EEM　results,　the　complexation　characteristics　of　SA　and　aluminum　varied　with　pH　value.　According　to　the　XPS　and　ESI-MS　results,　1:1　complexes　Al(OH)(C7H4O3)(H2O)2　formed　in　the　early　stage　of　CDC　process　with　initial　pH　5.　The　complexation　reaction　was　strong　so　the　stable　complexes　were　difficult　to　remove.　In　the　early　stage　of　CDC　process　with　initial　pH　6,　the　medium　polymer　Al　(such　as　in　situ　Al13)　formed　and　complexed　with　SA,　which　could　polymerize　with　added　aluminum　and　form　coral　reef-like　flocs　with　rough　surface　and　loose　structure.　As　a　result,　the　removal　of　SA　was　enhanced.　The　small　molecular　organics　were　removed　by　the　adsorption　of　floc　surface　at　initial　pH　7　due　to　the　formation　of　amorphous　aluminum　hydroxide.　©　2022　Chinese　Society　for　Environmental　Sciences.　All　rights　reserved.