In　chlorophenol　wastewater　treatment,　adding　easily　degradable　carbon　sources,　such　as　methanol,　ethanol,　sodium　acetate,　and　sodium　propionate,　significantly　improves　the　chlorophenol　removal　efficiency.　This　study　systematically　compares　these　conventional　carbon　sources　in　different　sequencing　batch　reactors　to　understand　their　specific　effects　on　both　2,4,6-trichlorophenol　(2,4,6-TCP)　degradation　efficiency　and　microbial　abundance.　In　a　35-day　experiment,　as　a　carbon　source,　ethanol　exhibited　a　lower　2,4,6-TCP　degradation　concentration　(77.56　mg/L)　than　those　of　methanol,　sodium　acetate,　and　sodium　propionate,　which　achieved　higher　degradation　concentrations:　123.89　mg/L,　170.96　mg/L,　and　151.79　mg/L,　respectively.　As　a　carbon　source,　sodium　acetate　enhanced　extracellular　polymeric　substance　production　(200.80　mg/g　center　dot　VSS)　by　microorganisms,　providing　protection　against　the　toxicity　of　chlorophenol　and　resulting　in　a　higher　2,4,6-TCP　removal　concentration.　Metagenomics　identified　crucial　metabolic　genes,　including　PcpA,　chqB,　Mal-r,　pcaI,　pcaF,　and　fadA.　The　abundance　of　genera　containing　the　chqB　gene　correlated　positively　with　the　metabolic　capacity　for　2,4,6-TCP.　Moreover,　small　molecular　carbon　sources　such　as　methanol,　sodium　acetate,　and　sodium　propionate　promoted　the　enrichment　of　genera　with　functional　genes.